Animation 1.3D measurement of self-healing material from Tosoh Corporation measured by digital holographic microscopy. The surface has been scratched by a metallic tool. Animation 2. Section of self-healing material recovering from a scratch Self-healing materials are artificial or synthetically created substances that have the built-in ability to automatically repair damages to themselves without any external diagnosis of the problem or human intervention.
Generally, materials will degrade over time due to fatigue, environmental conditions, or damage incurred during operation. Cracks and other types of damage on a microscopic level have been shown to change thermal, electrical, and acoustical properties of materials, and the propagation of cracks can lead to eventual failure of the material.
In general, cracks are hard to detect at an early stage, and manual intervention is required for periodic inspections and repairs. In contrast, self-healing materials counter degradation through the initiation of a repair mechanism that responds to the micro-damage.
1–2 Some self-healing materials are classed as smart structures, and can adapt to various environmental conditions according to their sensing and actuation properties. : 145 Although the most common types of self-healing materials are polymers or elastomers, self-healing covers all classes of materials, including metals, ceramics, and cementitious materials,
Healing mechanisms vary from an instrinsic repair of the material to the addition of a repair agent contained in a microscopic vessel. For a material to be strictly defined as autonomously self-healing, it is necessary that the healing process occurs without human intervention.
Contents
- 1 How is self-healing material made?
- 2 What is self-healing and how IT works?
- 3 What is self heal used for?
- 4 Where are self-healing polymers used?
- 5 What is another word for self-healing?
- 6 What is the difference between self-healing and repair?
- 7 What are the benefits of self-healing materials?
- 8 What are the types of self-healing concrete?
- 9 What is self-healing infrastructure?
- 10 Where is self-healing concrete made?
- 11 What are the three types of healing?
- 12 Where is self heal found?
- 13 What are the types of self-healing?
What materials are self-healing?
Abstract – Self-healing materials are polymers, metals, ceramics, and their composites that when damaged by an operational use has the ability to fully or partially recover its original set of properties. Self-healing is a bioinspired technology which can heal micro- or nanolevel cracks generated in polymeric composites without any external interventions.
In the present scenario, fiber-reinforced polymer (FRP) composites are being used in wide range of applications such as automobile, aerospace, energy, construction, and sporting equipment applications because of their high strength and stiffness-to-weight ratio, excellent corrosion resistance, and high thermal stability.
Delamination occurring between the interply region and poor fracture toughness of matrix is the main failure mode occurring in FRP composites. Delamination of FRP composites occurs due to micro- or nanolevel cracks generated during in service period which propagates and finally led to catastrophic failure of the material.
What does self-healing mean?
: acting or serving to heal or repair oneself or itself : such as. : involving or promoting recovery from injury or disease. the body’s self-healing ability/process.
What do you mean by self-healing concrete?
11.2.1 Self-healing Concrete – Self-healing concrete is mostly defined as the ability of concrete to repair its cracks autogenously or autonomously. It is also called self-repairing concrete. Cracks in concrete are a common phenomenon due to its relatively low tensile strength.
- Durability of concrete is impaired by these cracks since they provide an easy path for the transportation of liquids and gases that potentially contain harmful substances.
- If microcracks grow and reach the reinforcement, not only the concrete itself may be attacked, but also the reinforcement steel bars will be corroded.
Therefore, it is important to control the crack width and to heal the cracks as soon as possible. Self-healing of cracks in concrete would contribute to a longer service life of concrete structures and would make the material not only more durable but also more sustainable,
- Self-healing is actually an old and well-known phenomenon for concrete as it possesses some natural autogenous healing properties.
- Due to ongoing hydration of clinker minerals or carbonation of calcium hydroxide (Ca(OH) 2 ), cracks may heal after some time.
- However, autogenous healing is limited to small cracks and is only effective when water is available, thus making it difficult to control.
Nonetheless, concrete may be modified to build in autonomous crack healing, Dry started to work on the autonomous self-healing concrete in 1994, In the following years, several researchers started to investigate this topic. Many self-healing approaches are proposed.
- They mainly include autogenous self-healing method, capsule-based self-healing method, vascular self-healing method, electrodeposition self-healing method, microbial self-healing method, and self-healing method through embedding shape memory alloys (SMAs),
- For example, Edvardsen found that the greatest potential for autogenous healing exists in early age concrete,
Mihashi et al. used urea-formaldehyde microcapsules (diameter 20–70 μm) filled with epoxy resin and gelatin microcapsules (diameter 125–297 μm) filled with acrylic resin to achieve self-healing of concrete under compression and splitting, Joseph et al.
- Made use of an air-curing healing agent, provided by glass tubes.
- One end of the tubes was open to the atmosphere and curved to supply healing agent.
- When the tubes become depleted after concrete cracking occurred, additional agent could be added via the open end to allow healing of wider cracks,
- Otsuki et al.
proposed the electrodeposition method as a means of repair for cracked concrete structures and investigate the effects of this method on various concrete properties, Jonkers et al. investigated the potential of bacteria to act as self-healing agent in concrete, i.e., their ability to repair occurring cracks.
- They proved that application of bacterial spores as self-healing agent appears promising,
- Uang and Ou, and Li et al., found that the SMA wire as reinforcing bar can make cracks close and perform the task of emergency damage repair in concrete structures.
- The cracks are closed due to the super elastic behavior of embedded SMAs,
Read full chapter URL: https://www.sciencedirect.com/science/article/pii/B9780128005170000113
How is self-healing material made?
Meeting the challenges – A chemistry that meets these requirements remarkably well is the ring opening metathesis polymerisation (ROMP) of dicyclopentadiene (DCPD), catalysed by Grubbs’ catalyst (Scheme 1). Metathesis is a reaction in which two compounds with a similar functional group (usually a double or triple bond) exchange the components on each side of the bond to give new compounds ( ie A-B + C-D → A-D + C-B).
- Dicyclopentadiene is an inexpensive monomer that readily undergoes metathesis and is available as a liquid at room temperature.
- It has low viscosity and flows easily out of the microcapsules, yet it also has low enough volatility to remain in the crack and polymerise before evaporating.
- DCPD also has a long shelf life, owing in part to its relative insusceptibility to radical polymerisation.
All these properties are critical for successful self-healing. Scheme 1 – ROMP of dicyclopentadiene (DCPD) Figure 2 (a) – Dyed microcapsules containing DCPD before being ruptured Figure 2 (b) – Dyed microcapsules containing DCPD after being ruptured Another benefit of DCPD is its compatibility with the conditions used for microencapsulation in poly(urea-methanal). This process involves suspending the DCPD as small droplets in a rapidly stirred, acidic solution of urea in water.
Methanal is then added and the mixture is heated to 55°C.2 This causes a thin shell of poly(urea-methanal) to form around the DCPD droplets, thus encapsulating the liquid. The resulting microcapsules can then be filtered and dried to give a free-flowing, coarse powder. As seen in Fig 2, the capsules release a significant amount of DCPD when they are ruptured.
However, they are sufficiently robust to be incorporated into the epoxy resin without bursting. There are several catalyst systems, based on W and Mo complexes, that have been developed over the past three decades for the ROMP of DCPD and, as a result, polyDCPD has rapidly become a commercially important material, especially in moulding large parts for trucks, tractors and snow mobiles.
- One of the key reasons for the success of polyDCPD is its extreme toughness.
- The strained norbornene-like double bond reacts nearly quantitatively in ROMP, while the second, less strained cyclopentene ring opens on a fraction of the monomers to create a densely cross-linked material that is resistant to fracture (Scheme 1).3 The catalysts that were initially used for the ROMP of DCPD all have one major drawback that has prevented their use in self-healing.
They decompose in minutes or less when exposed to air, which greatly complicates the preparation of self-healing composites. Fortunately, the recently developed ruthenium alkylidene complexes – ie Grubbs’ catalysts – are capable of performing ROMP without the need to protect them from water or air.4 The ROMP of DCPD catalysed by Grubbs’ catalyst is rapid at room temperature and there is no need to control catalyst concentrations. Figure 3 – Self-healing sample during a fracture test The self-healing materials were originally prepared by mixing DCPD-filled microcapsules and crystals of Grubbs’ catalyst in an epoxy resin. The resin was then loaded into a silicone mould to create a sample with a tapered, double-cantilever beam geometry ( Fig 3 ).
The mould forms a groove in the centre of the sample to direct crack growth during testing, and the tapered shape is specifically designed so that the fracture toughness can be measured without taking into account the distance that the crack propagates in the sample.5 The testing begins by propagating an initial crack to measure the fracture toughness of the virgin material.
The crack faces are brought back together and the sample is set aside to heal for at least 24 hours. It is then fractured again to determine how much toughness has been recovered.6 The toughness of the healed sample divided by that of the original sample is defined as the healing efficiency.
Our initial materials showed significant fracture-toughness recovery, and healing efficiencies of up to 90 per cent could be achieved. However, to heal well, we had to include 2.5 wt per cent catalyst (relative to the epoxy), a catalyst loading requirement that is much higher than what would be expected based on the concentration needed to polymerise pure DCPD in non-self-healing situations.
Since Grubbs’ catalyst is relatively expensive, this high loading makes the material prohibitively costly.
What is self-healing and how IT works?
Self-healing refers to the process of recovery (generally from psychological disturbances, trauma, etc.), motivated by and directed by the patient, guided often only by instinct, Such a process encounters mixed fortunes due to its amateur nature, although self-motivation is a major asset.
What is self heal used for?
Other Name(s): All-Heal, Blue Curls, Brownwort, Brunelle, Brunelle Commune, Brunelle Vulgaire, Brunette, Carpenter’s Herb, Carpenter’s Weed, Charbonnière, Heal-All, Heart of the Earth, Herbe au Charpentier, Hercules Woundwort, Hock-Heal, Petite Consoude, Prunela, Prunella, Prunella vulgaris, Prunelle, Prunelle Vulgaire, Self Heal, Sicklewort, Siclewort, Slough-Heal, Woundwort, Xia Ku Cao.
Overview Uses Side Effects Precautions Dosing
Self-heal is an herb. The parts that grow above the ground are used to make medicine. Self-heal is used for inflammatory bowel disease (Crohn’s disease and ulcerative colitis), diarrhea, colic, and stomach upset and irritation (gastroenteritis). It is also used for mouth and throat ulcers, sore throat, and internal bleeding.
- Some people use self-heal for HIV/AIDS, fever, headache, dizziness, liver disease, and spasm.
- It is also used to kill germs (as an antiseptic), loosen phlegm (as an expectorant), and tighten and dry skin (as an astringent).
- Self-heal is applied directly to the skin for vaginal discharges and other disorders of women’s reproductive systems, as well as for wounds and bruises.
Be careful not to confuse self-heal with another plant called sanicle. Sanicle is sometimes referred to as self-heal, but it’s different.
Where are self-healing polymers used?
7.6 Conclusion – Self-healing polymers and composites are suitable materials for healing the cracks. Traditional methods of repairing process has some disadvantages, which are discussed in this chapter. Because of that, self-healing materials are best substitution for traditional repairing process.
- They are cost-effective and available.
- They are very effective for microcrack and internal damage, which are not healed by the traditional methods.
- There are some types of polymers that are applied as self-healing materials, which are mentioned as follows: electrically conductive, electromagnetic, electromechanical, magnetic, and thermally conductive polymer composites.
Self-healing polymer composites are categorized into two classifications: (1) intrinsic self-healing and (2) extrinsic self-healing. Each of them is divided into other categories. Each method has some benefits and disadvantages. For example, capsule-based self-healing heals small crack and vascular self-healing heals large area.
What is another word for self-healing?
What is another word for self-heal?
betony | bishop’s wort |
---|---|
bishopwort | common hedgenettle |
heal-all | hedgenettle |
lamb’s ears | lousewort |
purple betony | wild hop |
What is the difference between self-healing and repair?
MSI Repair and Self-Healing are both great features of msi. Self-Healing in particular is actually a life saver for apps with CurrentUser files/regs (aka Per User data). Many people think that MSI Repair and Self-Healing are the same, some will tell you they are NOT.
Imho they are not exactly the same but they are very SIMILAR, they both use MSI’s built in methods for efficiently checking and fixing possible issues with an installation. Repair: A Repair is essentially a reinstallation of the MSI, though this is a “smart” reinstallation. A Repair will re-install only portions of the application that are missing or broken, depending on the level of repair used (See MSI Command Lines).
Normally Repairs are started via Add/Remove, re-running the MSI (mannually or cmd line). Self-Heal: This is a method of checking an install, and starting a limited Repair if needed based on that check. Self-Healing uses “Advertised Entry Points”. I routinely use Advertised Shortcuts as an Entry Point for Self-Healing, other types can be used but I have not as of yet worked with them (MIME, File Associations etc).
When an Advertised Shortcut is launched, it will check the application/msi’s component Key files/entries, if any are missing it will start a LIMITED repair. You can easily tell and Advertised shortcut vs normal shortcut by looking at the properties. Advertised Shortcuts will grey out the Target path, while normal will NOT.
The following was posted by jmcfadyen on Appdeploy.com forum, It is a VERY good explanation of how Self-Healing works, at the end even tells how to drastically speed up Self-Healing for only Per User data Features: A feature is a container which may hold other features and components.
- Component: A component is a container designed to hold application related information such as: regsitry keys files ODBC configuration to name a few.
- A component has a unique identifier called a which is represent by a 32 bit HEX code.
- Eypath: The keypath is an item in a component which is checked during advertised actuation.
Entry Points: Items within the package can be advertised. It is common to use shortcuts and file extensions as advertised entry points. An advertised entry point will trigger the checking of primary keys for components within a feature. I will outline a little more exactly how healing works which will assist in understanding why to use the following feature / component structure.
For the following assume there is only one Feature called “COMPLETE” and a few components such as “COMPONENT1” “COMPONENT2” and “COMPONENT3” COMPONENT1 contains 1 file “FILE1.TXT” with a primary key of “FILE1.TXT” COMPONENT2 contains 1 file “FILE2.TXT” with a primary key of “FILE2.TXT” COMPONENT3 contains 1 advertised shortcut “SHORTCUT1” contains 1 file “FILE3.TXT with a primary key of “FILE3.TXT” contains 1 file “FILE4.TXT COMPONENT4 contains 1 HKCU reg key with a primary key of “HKCU\test” When an entry point such as a shortcut is triggered in an MSI the following will occur.
The msi self healing operation will begin its checking process in the following manner. The MSI will enumerate what feature the entry point or in this case the shortcut belongs to. For the above example assume a user runs SHORTCUT1 which is the advertised entry point.
- This action will cause the MSI to find out what FEATURE SHORTCUT1 is in.
- The next step is to find out what other components are in this feature.
- In this case COMPONENT1 COMPONENT2 and COMPONENT3 Each of the COMPONENTS in the same feature as the entry point will be checked.
- The primary key of each component will then be checked against the workstation to ensure that these primary keys exist.
In this case COMPONENT1 has a primary key of FILE1.TXT therefore the msi will check if FILE1.TXT exists on the workstation and continue this process through all of the COMPONENTS within the same FEATURE the entry point is in. If any of the PRIMARY KEYS are missing the entire feature is healed.
- As depicted above if FILE4.TXT is missing nothing will happen.
- FILE4.TXT is not a primary key therefore the MSI will not care if it does not exist.
- Now a very important thing to note here is if there are any parent FEATURES windows installer will then step into the parent FEATURE and being this process again and continue until all parent FEATURES are checked.
Now for the interesting part. Anyone whom has been packaging for a while will know that HKCU registry keys are often the cause of trouble within a package. The current user keys normally are only delivered the user whom is logged in at the time of installation.
The msi technology has attempted to overcome this shortcoming and uses self healing to configure current user settings for all users of a given workstation. When using Wise Package Studio the default actions within Wise will create a COMPONENT called “CurrentUser” this component will have all of the HKCU registry keys inside it.
If your using other applications such as InstallShield I expect you could achieve the same results relatively easily. Now assuming we followed default configuration of Wise all of our components would go into the “COMPLETE” FEATURE including the aforementioned “CurrentUser” COMPONENT.
If you were to use this default methodology any new users logging into a machine and running an advertised entry point would trigger the healing mechanism’s checking routines. This would eventually get to the “CurrentUser” COMPONENT and would find that the primary key for the “CurrentUser” COMPONENT would not exist.
This in turn would trigger a heal of the entire COMPLETE FEATURE. Now on a small application this may be acceptable however if you have a 600mb application reinstalling the entire application for a new user would probably be extremely excessive. So to counter this effect with the help of some of the mentioned persons this idea was developed.
Create a new FEATURE STRUCTURE as follows: FEATURE “CurrentUser” Move your “Complete” FEATURE to a child of the “CurrentUser” FEATURE. so you will have the following. CurrentUser – – —Complete Whenever you have an application which contains HKCU components put the HKCU components into a COMPONENT called “CurrentUser” and put that COMPONENT into your “CurrentUser” FEATURE.
The remainderof the application would go into your COMPLETE FEATURE as pictured below. Feature:CurrentUser Component: CurrentUser – —-Feature:Complete – – Component: Component1 – – Component: Component2 – —- Component: Component3 Now in this scenario if you run the SHORTCUT1 as per the previous example the COMPLETE FEATURE is checked as per normal windows installer operation.
- In a good package this will not result in healing of the COMPLETE FEATURE as it should already be delivered during install time.
- But what is good about this is that once the COMPLETE feature is finished its checking routine Windows Installer behaviour steps up to the parent FEATURE in this case “CurrentUser” and checks that feature also.
If a new user is logged in the primary key for the “CurrentUser” COMPONENT will not exist which will trigger healing on the “CurrentUser” FEATURE therefore effectively you are now only healing a tiny portion of your package not the entire application.
Current User Healing II If you have not already read my first post this probably wont make alot of sense. Therefore I would recommend reading Current User healing before continuing with this. This assumes you know how healing works and understand fully keypaths and components etc. For those of you whom have read my first post on HKCU registry healing.
Here is the next step which will enable you to heal files as well as HKCU keys. If you have followed the first step which creates a feature structure in the following manner. HKCU – (Current User Feature) – Complete (Remainder of application) Your HKCU feature will only contain CurrentUser components or components which contain registry entries which are destined for the HKCU registry hive.
The complete feature will contain the main application including all “program files\%appname%” and HKLM entries. The reason for this is explained in the first Current User healing guide. Now to make full advantage of this method of healing often you are required to put files into the users profile directories such as “c:\documents and settings\%username%\application data” or similar folders such as “my documents” etc.
This is a way to allow you to heal this folder for each user, without requiring to step outside of the msi to maintain the healing process. Therefore no need for active setup or other methods, this is all fully self contained within the msi. To understand how this works its important to know how the duplicate file table works within the msi.
The duplicate file table is used to reduce the size of an msi and increase performance by not replicating files inside the msi. For example if you have a file in your package in the following locations which is identical the default behavious of msi is to not add this file again.i.e. c:\program files\%appname%\folder1\file1.txt c:\program files\%appname%\folder2\file1.txt here we have 2 files with the same name and structure.
Under normal conditions the msi would recognise this file is the same and it would make an entry in the duplicate file table. If we assume in the above example,\folder1\file1.txt was the first file to be placed into this msi it would then show in the file table as a normal file as expected.
However when we add,\folder2\file1.txt what you would expect is that another entry would be added to the file table as per the previous entry. However if the msi recognises the file is identical it does not use another entry in the file table instead it creates an entry in the duplicate file table. The duplicate file table then makes a pointer back to the first location where this file was installed to.
Therefore,\folder1\file1.txt was the first entry so instead of,\folder2\file1.txt being added again it uses the duplicate file table and makes a reference back to the install directory of the first file1.txt. In this case “c:\program files\folder1\file1.txt”.
What this means is that,\folder2\file1.txt does not get installed from the cabs of the msi but installed directly from its first install directory. In other words the,\folder1\file1.txt is copied to,\folder2\file1.txt. Hopefully that hasn’t confused you too much :-). The next step is to do this. As with the first guide I wrote you create your feature structure with the HKCU feature at the top of the tree.
You then do this. HKCU – (CurrentUser components) – – Complete Feature (remainder of app) We now create a folder under or “C:\program files\%appname%\_user” or whatever naming convention you like. I like “_user”. We then add any files into this folder that we would like to be delivered to the users profile.
- For example if you want “C:\documents and settings\%username%\application data\file1.txt” then we would create the following.
- C:\program files\%appname%\_user\application data\file1.txt” and so on.
- For each file that you want to be healed by this method you need to have the same file delivered to “C:\program files\%appname%\_user” Once you have completed this you then add those same files again into the normal locations of “c:\documents and settings\%username%” however this time the duplicate file table comes into play!!!.
These files that are being added for the 2nd time are recognised as already being in the package and the follow the same rules as above with the duplicate file table. Therefore they have entries in the duplicate file table instead of the file table. This also means that these files are healed from the local machine and not from the MSI.
- This has a few benefits, one is that you do not require the MSI to be present during healing time.
- So if you haven’t got a connected source it gets around that issue (mind you I am not saying don’t use ) Its just a workaround if needed.
- Now the final touch is to move all the components that were created during this step into the HKCU feature, my preference is to put the files in the same component as the HKCU registry entries that were created via the first guide.
This is because the duplicate file components do not have keypaths therefore technically dont have a healing reference. Hence putting them in the HKCU component ensures a heal for each new user. Therefore you would have the following configuration. HKCU – CurrentUser (component) – Contains = HKCU registry – = Duplicate File infomation – Complete – All other components This means that HKCU is at the top of the tree and contains both the CurrentUser components containing the HKCU registry entries.
And the duplicate file table entries are in the same component. The complete feature just contains the main application. Putting it all together. When you run the application and a user has not logged on before the HKCU entries are not present. Therefore when advertising is run from the complete feature the Complete feature is checked, all component keypaths are checked if something is missing from the Complete feature it is healed in its entirety.
As per normal the MSI will then step up the tree and run the checking functionality as per before. However in this instance as the advertising is downlevel from the HKCU feature the healing process changes slightly and steps into what is classed as Component level healing.
What are the benefits of self-healing materials?
SHMs are a class of smart materials with the propensity to autonomically and spontaneously repair themselves and recover their functionality after being damaged. With such materials, one can envisage extremely durable and reliable materials with low maintenance costs.
What are the materials used in self-healing concrete?
3.4 Mineral admixture in autogenous self-healing – Supplementary cementitious materials (SCMs) and expansive minerals compatible with cement can improve the self-healing capacity of concrete. Depending on minerals, it can serve either or both functionalities, that is, to remain considerably un-hydrated after the initial mixing stage, and to produce compatible expansive hydrated compounds that can heal cracks,
Minerals | Composition | Damage type | Curing condition | Performance (healed crack width in time etc.) | Source |
---|---|---|---|---|---|
CSA, a H, b A, c L, Mont. | Up to 10% (concrete) | 3 PB, mechanical | Water | 160–220 μm in 33d Calcite, CASH | |
CSA | 4.44 and 15.24% of cement (concrete) | Tension force | Still/continuous flow water | Reduced flow in 100 μm cracks, continuous flow is efficient | |
CSA, CA, a H, b A, c L, Mont. | PC with 10% CSA and 1.5% CA | Sp. tensile test | Water | 100–400 μm in 56 d Calcite | |
Silica, d CEA, bentonite, CA | 8% individual combination up to 14% | Compression, sp. tensile | Water, wet-dry, air, freeze–thaw | 220 μm in 2 weeks d CEA (individually efficient) silica, bent., CA (combination is efficient) | |
FA, SF, CA | OPC, OPC + 30%FA, OPC + 10%SF, OPC + 1%CA | Splitting tensile test | Water | 50 μm in 12d larger cracks heal efficiently with SF | |
FA | 15–20% with PC (paste) | Shrinkage microcracks | Water | Meso-macro pores at 91, 182 and 364 d | |
FA | 5–15% wt. of sand (concrete) | Freeze–thaw | Water | Improve e DME over 90% in 28d | |
BFS | OPC + 50% BFS | Mechanical | Water | Product formation is three times faster for CEM I | |
FA, slag | 30–40% of cement (mortar) | Shrinkage | Water | Improvement in compressive strength | |
c L, slag, FA | 30, 50% FA; 50, 75, 85% slag (paste/mortar) | 3 PB, mechanical | Water | 200 μm in 42d | |
Slag | 66% of cement (paste) | Sliced, mechanical | Ca(OH) 2 solution | 60% of 10 μm in 240 h C-S-H, ettringite, hydrogenate etc. | |
Bentonite | Nanoclay in mortar as internal water reservoir | Mechanical | Water | Enhanced hydration for self-healing | |
Bentonite, slag, c L | 2% PVA by vol. Length = 8 mm, dia = 40 μm | 4 PB | Water, wet-dry cycle, air | Nanoclay improves the reloading deflection capacity | |
Quicklime, FA | (3%) on fly ash-PC cement pastes | Mechanical | Water | Increased SiO 2 solubility extra Ca(OH) 2 | |
Expanded clay LWAs | Na-MFP and PC coated (mortar) | Mechanical | Water | Absorption decrease sodium, phosphorous and fluoride, CH | |
CSA | PVA coated, up to 10% by wt. of cement (mortar, 1:3) | 3 PB | Water | <100 μm in 11d, 100–200 μm in 14d, >200 μm in 16d | |
CA: cement + sand + microsilica | 1–2% of cement | 4 PB | Water, open air | 60% cracks sealed under open air condition | |
MgO | 4–12% of cement | Drying shrinkage, 3 PB | Water | <500 μm in 28d durability improved |
What are the types of self-healing concrete?
Autogenous self-healing crack Self-healing concrete is characterized as the capability of concrete to fix its cracks on its own autogenously or autonomously. It not only seals the cracks but also partially or entirely recovers the mechanical properties of the structural elements.
This kind of concrete is also known as self-repairing concrete. Because concrete has a poor tensile strength compared to other building materials, it often develops cracks in the surface. These cracks reduce the durability of the concrete because they facilitate the flow of liquids and gases that may contain harmful compounds.
If microcracks expand and reach the reinforcement, not only will the concrete itself be susceptible to attack, but so will the reinforcement steel bars, Therefore, it is essential to limit the crack’s width and repair it as quickly as feasible. Self-healing concrete would not only make the material more sustainable, but it would also contribute to an increase in the service life of concrete structures and make the material more durable and environmentally friendly.
Self-healing is an old and well-known phenomenon for concrete, given that it contains innate autogenous healing characteristics. Cracks may heal over time due to continued hydration of clinker minerals or carbonation of calcium hydroxide, Autogenous healing is difficult to control since it can only heal small cracks and is only effective when water is present.
This limitation makes it tough to use. On the other hand, concrete may be altered to provide self-healing capabilities for cracks. There are many solutions for improving autogenous healing by adding the admixtures, such as mineral additions, crystalline admixtures, and superabsorbent polymers,
What is self-healing architecture?
We can help you to: –
Set up the most suited self-healing architecture for your system Deploy your self-healing system based on a Kubernetes framework Log and monitor failures efficiently, so you can obtain operational insights
Keeping a software system, consisting of multiple interconnecting components, operational 24/7 is challenging. So, when a component fails and downtime is looming, your support team needs to kick into action. However, keeping a 24/7 maintenance team or support line on call can be expensive.
What is self-healing infrastructure?
This post:
- Highlights features found in Red Hat Insights and Ansible Automation Platform that can be used as part of a self-healing infrastructure.
- Walks through an example architecture triggering Advisor events via Insights Notifications service, using a middleware layer for connecting both applications, then launching an automation job template to remediate the detected issue.
Self-healing infrastructure brings together monitoring, streaming, intelligence and automation so that organizations can respond more quickly to datacenter events, reducing operational toil and improving reliability while, to a reasonable degree, minimizing human intervention.
Where is self-healing concrete made?
How does self-healing concrete work? – Basilisk Self Healing Concrete is developed at the Delft University of Technology and is an autonomous repair system that works with limestone-producing micro-organisms (bacteria). If the bacteria come into contact with oxygen and water, they will convert nutrients to calcium carbonate (limestone).
What are the three types of healing?
Primary healing, delayed primary healing, and healing by secondary intention are the 3 main categories of wound healing.
What are the two types of healing?
Wound Healing Cutaneous wound healing is the process by which the skin repairs itself after damage, It is important in restoring normal function to the tissue. There are two main types of healing, primary intention and secondary intention, In both types, there are four stages which occur; haemostasis, inflammation, proliferation, and remodelling.
How do you process self-healing?
How to Dry – Drying self heal is super easy. All you need to do is gather the top portions of the plant – flower, stem, and leaves – and spread them out in a single layer over a screen, paper towel, or clean dish towel. Allow to air dry for several days or until completely dried.
- Store in a paper bag or glass jar out of direct sunlight.
- Eep the herbs whole and only crumble up right before using, in order to keep them fresh longer.
- Use for teas and salves – recipes can be found below.
- Shelf life of dried self heal is around 9 months to a year, or as long as the herb has a good color and scent.
Drab faded herbs have lost potency and should be composted. self heal flowers, stems, and leaves air drying on a screen
Where is self heal found?
Self-heal, common selfheal, carpenter-weed • Prunella vulgaris –
Photos by John Reynolds (left), Mary Vasey (top right), and David Norwell (bottom right). |
Identification Self-heal is a perennial wildflower which grows 10-50 cm tall. The flowers are purplish to pink ( occasionally white ), 1-2 cm long, and short stalked. They form a dense spike-like cluster at the top of the stem. The petals are fused into a 2-lipped tube ; the upper tube is hooded while the lower is lobed.
- The sparse leaves grow in opposite pairs along the step, are lance- to egg-shaped, and have smooth to barely-toothed edges.
- Habitat & Range Common at low to middle elevations, self-heal grows well in damp soils including meadows, clearings, lawns, and forest edges.
- It is a common species throughout most of BC, and is found throughout temperate climates in the rest of North America as well as Eurasia.
There are two subspecies of Prunella vulgaris : ssp. lanceolata, and ssp. vulgaris, The former is native to North America, while the latter was introduced from Eurasia and has since naturalized in North America. The two can be differentiated by leaf shape and other characteristics.
- Human Uses Self-heal has a long history of medicinal use and is known for its anti-viral, anti-bacterial, anti-inflammatory, and anti-allergenic properties.
- Traditionally the Nuxalk boiled the whole plant for the heart, and the Quinault and Quileute put the juice on boils and wounds.
- According to the 16th-century herbalist John Gerard, “there is not a better wounde herbe in the world.” The whole plant can be applied to a wound to promote healing, and the dried leaves can be made into a tea to treat indigestion and as a general detoxifier.
Click here for more details of this plant’s medicinal uses. Aside from its medicinal properties this plant is also a tasty addition to salads. iNaturalist https://www.inaturalist.org/taxa/52764-Prunella-vulgaris References Bramley, G. Prunella vulgaris (selfheal),
Science and Conservati on. Kew Royal Botanical Gardens. Accessed 14/11/2014. Fang X, Chang RC, Yuen WH, Zee SY. (2005). “Immune modulatory effects of Prunella vulgaris L”. International Journal of Molecular Medicine.15 (3): 491–496. DOI: 10.3892/ijmm.15.3.491, Pojar, J and MacKinnon, A. (2005). Plants of Coastal British Columbia, Revised,
Vancouver, BC: Lone Pine Publishing.P.246. Authors and editors of page Paige Whitehead and Brian Starzomski (2014).
What is the first step in self-healing?
7 Steps to Self-healing Whenever I speak to my patients about self-healing they usually look at me with that perplexed look that says “you’re the doctor, you spent all those years in training if I thought I could do it myself I wouldn’t be here!” When I tell them that they are responsible for their own healing, they sometimes start to object until I explain that we go through every day expecting our bodies to heal themselves – why wouldn’t we expect that to apply to all aspects of our pain? Self-healing isn’t as complicated as you may think.
- Tuning our attention and energies toward self-healing is easy, quick, and can actually change our emotions and speed our healing in a few moments.
- We Are All Self-Healing Eastern and ancient medical models have been based on self-healing for thousands of years.
- We witness our body’s ability to heal itself when small cuts heal when bones grow back together and with our expectation, “this will heal.” When we tune in to our bodies with intention we can truly change our lives physically, mentally, emotionally, and spiritually.
Self-healing is not at all complicated. In a few simple steps, you can bring a feeling of peace into your body. You can tune into your body and direct your thoughts and emotions to make changes. It is a simple as changing the channel from bad news on a 24-hour-a-day news channel to your favorite comedy show and feeling yourself relax with that change.
It’s similar to when you’re feeling sad but not being able to cry so you watch a sad movie to get that release. You can choose to change your day and move in a new direction try learning to invite ease, flow, and even “miracles” into your life.7 Simple Steps to Self-Healing Please read through all steps and then, when you’re ready, give it a try.
It doesn’t cost a thing! 1. Decide that you’re ready to try self-healing. In order to self-heal, you must be 100 percent willing and ready to be healed. Everyone is ready in their own time, and there is no judgment on what constitutes feeling ready, however, usually, there is a strong sense of knowing that you are ready to let it all go.
Along with feeling ready you also have to allow yourself to be open to the possibility of being healed. Once you have opened yourself to the possibility, you then have to step back and let it happen.2. Sit in a comfortable position and become aware of your breath. There’s no need to change the pattern of your breathing – just pay attention to the flow – in and out, in and out.
No judging it, no changing it – just noticing. This is simply to become “present” and to stop some of the never-ending thoughts from interfering for the next few minutes. If at any time, you get distracted, as we all do, don’t think “I’m just no good at this,” just go back to thinking about your breathing.
- It’s always there to retrain your focus.3.
- Take your hands (palms together) in front of you and rub them together quickly for 30 – 60 seconds.
- Let them become warm from the friction and feel that warmth.
- Invite a slight smile in as you are rubbing your hands and taking this time.
- Smiling itself is healing and has the ability to switch our moods in a few seconds.4.
Hold your hands 6-8 inches away from each other, facing each other, and feel the energy flowing through them. This energy is always there – you are just feeling it now because you set the intention of awakening your awareness to it.5. Close your eyes. Start imagining this energy as a golden light that is expanding and surrounding your entire body.
- Imagine this golden light traveling up through your body from your toes to your head.
- As the light surrounds you, imagine it going into your body through the top of your head and down through your spine.
- See if you can move the energy up your arms, through your body.
- There is no “wrong way” to do this.
You are simply awakening your attention to this energy that is always there. Now pair that with your intent feel and to heal. If you feel like you are losing touch with feeling the energy – rub your hands together again.6. Notice the energy affecting the parts of the body it flows into.
- As you watch the golden light passes through your body, imagine it healing and clearing everything that no longer serves you.
- Consider asking the light to heal and cleanse everything that no longer serves you.
- Allow your breathing to get deeper and deeper and as you clear things with the golden light, allow yours exhales to become longer and deeper, as if you are pushing out the stagnant energy.
Continue this for 10 minutes or so. Allow yourself to feel any emotions or blocks that arise and try to push past any ego-driven thoughts or distractions.7. Thank you for taking just a tiny bit of time to learn this new and important skill. Thank your body for being able to awaken to this awareness and healing.
- Playing” with this energy flow for even five or ten minutes can bring a state of joy and peace that you may have felt was impossible even minutes earlier.
- Once you have completed your mediation, say a little prayer or blessing to your higher self, those who care about you and God (if this feels right to you), and ask them to help you to heal and release all that no longer serves you.
Ask them to support your ability to self-heal. Call it to different parts of your body. Notice how it feels as it reaches different spaces. How did that feel? Ask yourself if you feel any different from when you started. Either way, keep practicing. I promise – every little bit helps! Interested in learning more? Attend our workshop with Emily Miranda-Thompson: “Self-Healing through Movement, Meditation and Loving-Kindness” this Saturday, May 5th from 10 am – 12 pm.
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But how do you find the right expert? Learn more about various types of psychotherapy and what issues they address. Is the stress of wanting to conceive and undergoing treatments affecting your everyday life? Learn more about how infertility can lead to depression and find out what you can do about it.
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Do you suspect your child’s behavior can be explained by ADHD? Learn more about ADHD signs, and find out what steps you can take to improve your child’s symptoms and help them live a happier life. : 7 Steps to Self-healing
Is there self-healing fabric?
Self-healing fabrics are designed to heal from damages that occur during daily use, such as rubbing, sunlight exposure, etc. In this context, Martindale abrasion tests are widely used to simulate fabrics’ daily wear due to abrasion and wear.
What are the types of self-healing?
Self-healing polymers are an artificially developed polymer that are capable of repairing damage to a variety of building materials on their own, without the need of human intervention. Self-healing polymers are making such an impact on both social and commercial levels that they have revolutionized the market. There are two different types of self-healing polymers: intrinsic and extrinsic.
Intrinsic: Polymers that don’t need an external agent to repair damage. Extrinsic: Polymers that when mixed with an external agent that’s put inside the matrix, can repair damage.
The Use of Self-Healing Polymers All building material ends up with small structural damages as time passes. There are a variety of ways to repair these cracks, but most of them require routine checks, which are impractical from a time and money standpoint.
- Self-healing polymers integrate seamlessly with the material, and their self-healing properties eliminate the need for temporary fixes and human inspection.
- Because self-healing materials require less infrastructural maintenance, last longer, reduce the need for replacements and are better for the environment, the industry has been steadily rising.
Thanks to the advancements in the materials that have been made in the recent past, they are being used in a variety of industries, including construction and aerospace. Intrinsic Self-Healing Polymers Intrinsic self-healing materials are composed of a variety of polymers that restore their own structural integrity without any need of outside help.
- This occurs because there is local increase in the mobility of the polymeric chains, which allows cracks to be repaired on their own.
- Thanks to this feature, the demand has grown amongst consumers.
- The self-repair that intrinsic self-healing polymers form is possible due to the reduction of the material viscosity and internal and external stimulus, such as pH changes or irradiation.
To ensure good mechanical and physical properties of the polymers, there are a lot of factors to consider. These include cluster distribution and size, crystallinity as well as molecular eight. Extrinsic Self-Healing Polymers Extrinsic self-healing polymers differ from their intrinsic counterparts because they require an external agent to trigger them to repair infrastructural damage.
They also help increase the lifespan of construction materials that are prone to crack. Not only does the polymer heal the crack, it reinforces the surrounding material to prevent the crack from spreading. The healing agent can be blended as a solid into the polymer or added in liquid form via capsules.
It is released when the cracks in the material rupture the containers the agent is held in. Self-Healing Polymer Market Forecast Self-healing polymers are able to transform physical energy into a chemical response to fix damages in building materials.
According to the USA Green Building Council, the green construction material and service market will grow at 13% through 2020. The green construction accounts for 22% of the total commercial construction in the U.S. in 2018. The market for North America is predicted to grow at 27% through 2024.
Want to learn more about the polymer market? Self-healing polymers are a growing industry. They are impacting a variety of markets and will branch into more markets as the technology develops. Learn more about them in the following articles: Global Self-Healing Market Report Self-Healing Polymers and Shopping Malls Clara Mouawad on Oct 30, 2019 10:00:00 AM Clara Mouawad is the content writer at BCC Research.
Why are some metals considered self-healing?
Technology Overview: – This healing cellular metal is a new structural material that can continuously self-repair cracks and redistribute cellular materials within itself at room temperature. This material is capable of reinforcing itself through the path of stress within the member while under standard conditions.
What body parts can heal themselves?
The liver is the only organ in the human body that can regenerate. Although some patients who have a diseased portion of their liver removed are unable to regrow the tissue and end up needing a transplant. Researchers from Michigan State University believe blood clotting factor fibrinogen may be responsible.
For most patients with liver disease, a surgeon can perform a liver resection and remove the diseased portion of the liver before allowing the patients’ body to regrow this portion of liver. However, this is not the case with all patients; some will require a liver transplant following the resection because their liver tissue does not re grow.
Until now it has been unclear why this is the case, but researchers from Michigan State University believe the blood-clotting protein fibrinogen is the key. After the diseased portion of the liver is removed, fibrinogen and blood platelets accumulate in the remaining liver, which triggers the earliest stages of regeneration.
If fibrinogen levels are low in patients, the number of platelets in the liver is lower, which means slower regeneration, and a higher chance of needing a transplant. In the future, a simple blood test could help doctors determine if liver resection patients will successfully regrow their own tissues or would benefit from fibrinogen concentrated being administered during surgery.
Source: EurekAlert Read more: : The liver is the only organ in the human body that can regenerate. Although some patients who have a diseased portion of their liver removed are unable to regrow the tissue and end up needing a transplant. Researchers from Michigan State University believe blood clotting factor fibrinogen may be responsible.