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Living organisms are open systems that can incorporate externally provided nutrients to vary their appearances and properties, while synthetic materials normally have fixed sizes, shapes, and functions. Herein, we report a strategy for enabling cross-linked polymers to continuously grow with programmable bulky structures and properties. The growing strategy involves repeatable processes including swelling of polymerizable components into the cross-linked polymers

Developing a novel strategy to synthesize photoresponsive polymers is of significance owing to their potential applications. We report a photoinduced strain‐assisted synthesis of main‐chain stiff‐stilbene polymers by using ring‐opening metathesis polymerization (ROMP), activating a macrocyclic π‐bond connected to a stiff‐stilbene photoswitch through a linker. Since the linker acts as an external constraint, the photoisomerization to the E‐form leads to the stiff‐stilbene being strained and thus reactive to ROMP. The photoisomerization of Z‐form to E‐form was investigated using time‐dependent NMR studies and UV/Vis spectroscopy. The DFT calculation showed that the E‐form was less stable due to a lack of planarity. By the internal strain developed due to the linker constraint through photoisomerization, the E‐form underwent ROMP by a second generation Grubbs catalyst. In contrast, Z‐form did not undergo polymerization under similar conditions. The MALDI‐TOF spectrum of E‐form after polymerization showed the presence of oligomers of >5.2 kDa., A polymer with several photoresponsive units is reported, which is of a great significance owing to the excellent stimuli‐response behavior. A photoinduced strain‐assisted ROMP of a macrocyclic π‐bond connected to a stiff‐stilbene through a linker is described. As the linker acts as an external constraint, photoisomerization to the E‐form causes stiff‐stilbene to be strained and thus to be reactive toward ROMP, resulting in a polymer with multiple stiff‐stilbene units.

The development of lipid nanoparticle (LNP) formulations for targeting the bone microenvironment holds significant potential for nucleic acid therapeutic applications including bone regeneration, cancer, and hematopoietic stem cell therapies. However, therapeutic delivery to bone remains a significant challenge due to several biological barriers, such as low blood flow in bone, blood-bone marrow barriers, and low affinity between drugs and bone minerals, which leads to unfavorable therapeutic dosages in the bone microenvironment. Here, we construct a series of bisphosphonate (BP) lipid-like materials possessing a high affinity for bone minerals, as a means to overcome biological barriers to deliver mRNA therapeutics efficiently to the bone microenvironment

Both phototriggered growth and removal of polymer chains from surfaces are efficient ways to finely tune interface properties. Combining these two capabilities in one system with independent control can significantly increase the feasibility of photoregulation on surface modification but has not been reported yet. Herein we describe a novel approach to control both the growth and the detachment of polymer brushes independently by light with different wavelengths. The approach is based on a nitrodopamine-based initiator (NO2–BDAM) which contains a catechol structure for surface modification, alkyl bromide group for radical polymerization, and o-nitrophenyl ethyl moiety for photolysis. When dimanganese decacarbonyl (Mn2(CO)10) was applied together with NO2–BDAM as an initiating system, visible light (460 nm) can be used to trigger the site-specific growth of polymer brushes. Resulting polymer brushes can be selectively removed by UV light (360 nm). This method is suitable for different monomers on various s...

Natural organic structures form via a growth mode in which nutrients are absorbed, transported, and integrated. In contrast, synthetic architectures are constructed through fundamentally different methods, such as assembling, molding, cutting, and printing. Here, we report a photoinduced strategy for regulating the localized growth of microstructures from the surface of a swollen dynamic substrate, by coupling photolysis, photopolymerization, and transesterification together. Photolysis is used to generate dissociable ionic groups to enhance the swelling ability that drives nutrient solutions containing polymerizable components into the irradiated region, photopolymerization converts polymerizable components into polymers, and transesterification incorporates newly formed polymers into the original network structure. Such light-regulated growth is spatially controllable and dose-dependent and allows fine modulation of the size, composition, and mechanical properties of the grown structures. We also demonstrate the application of this process in the preparation of microstructures on a surface and the restoration of large-scale surface damage., Natural organic structures forms via a growth mode unlike synthetic architectures that are constructed through assembly, molding, cutting, and printing. Here the authors show a photoinduced strategy for regulating localized growth of microstructures from the surface of a swollen dynamic substrate.

This smart storage and washing integrated cabinet based on sine mechanism mainly includes three functional modules: cleaning, storage and transportation. Each part of the organization to cooperate with each other to achieve three basic functions, such as no dead-end dishwashing, tableware storage and according to the instructions to take dishes. Not only that, it also enables additional functions such as drying disinfection and residue filtration. Now that intelligence is rapidly spreading, people’s hands in tableware management are free , Let people only participate in the beginning and end of the tableware management chain, and provide greater convenience to people’s lives.

Wallpaper was introduced into China in the late 1970s. As an important interior decoration material, it has gradually consolidated its development position in the Chinese market in the past 40 years. As far as the current development is concerned, the number of wallpaper production lines has exceeded 1,000 in China, producing more than 800 million square meters of wallpaper, accounting for about 20% of the total global wallpaper production. The economic output value is considerable, and the steady increase in sales has long been overwhelming. Compared with other wall decoration materials, wallpaper is more cost-effective, cheaper, and easy to construct, has a variety of patterns, and is easy to replace. Therefore, some rational consumers will choose to use wallpaper to decorate the walls. But posting wallpapers often requires the cooperation of two people, wasting time and energy. At the same time, when the wallpaper is posted, it cannot be posted well when encountering obstacles. Therefore, it is more convenient and faster to design an adjustable semi-automatic wallpaper sticking machine. Moreover, compared with various automatic wallpaper sticking machines in the laboratory stage, this design is more portable and economical, which better caters to the needs of users who stick wallpaper by themselves, and reduces the difficulty of using it in the process of sticking wallpaper by themselves.

Two Ta-2.5W alloy sheets were cold-rolled to 1 mm and 0.5 mm thick and their plastic strain ratio (r values) were evaluated by tensile tests. The 0.5 mm sheet, comparing with the 1 mm sheet, showed a stronger variation of the r value. This is because that the {0 0 1}〈1 1 0〉 texture, as revealed by the EBSD, significantly increased in the 0.5 mm sheet, which led to the decrease of r value and the increase of anisotropy (Δr) and in turn the deterioration of deep drawing properties. An analytical model was established to correlate the microstructure evolution and the macroscopic r value.

The development of a smart antibacterial surface that can both kill attached live bacteria and release dead bacteria is reported. The surface consists of counterion-responsive poly(cationic liquid) brushes of poly(1-(2-methacryloyloxyhexyl)-3-methylimidazolium bromide) (PIL(Br)), the properties of which can be switched repeatedly between bacterial killing and bacterial release. Upon counter-anion exchange of PIL(Br) chains using lithium bis(trifluoromethanesulfonyl) amide (LiTf2N) to yield PIL(Tf2N), the wettability of the surface changes from hydrophilic (water contact angle ∼52°) to hydrophobic (∼97°). The PIL(Br) chains adopt an extended conformation with bactericidal properties. Counter-anion switching to PIL(Tf2N) gives a collapsed chain conformation allowing the release of killed bacteria. The switchable killing and releasing actions of the surface were maintained over three cycles. Thus it is concluded that PIL(Br) layers provide a viable approach for the fabrication of "smart" antibacterial surfaces.

With the intensification of the aging of our country’s population, the health care of the elderly has become a social problem that must be solved in my country. Elderly people often suffer from chronic diseases and need long-term medication. However, it is difficult for the elderly to take medicines on time and in doses due to deterioration of their physical functions. Based on the above background, the project team researched and designed a smart medicine box that can intelligently remind and automatically dispense medicine. The device is mainly divided into four functional modules: medicine dispensing module, medicine taking module, medicine dispensing module, and control module. It realizes the five basic functions of medicine addition, temporary storage and sealing, medicine absorption, automatic medicine dispensing, and timing reminder and Additional features such as data sharing.

Today, when energy problems are increasingly prominent, the development and utilization of solar energy has become the focus of achieving sustainable energy development. However, due to the dispersion of solar radiation energy and atmospheric absorption, the radiation intensity directly reaching the surface of the earth is relatively weak. The existing linear Fresnel concentrators in engineering are huge in size and have low concentration ratios. In order to increase the concentration ratio of the CSP device, the pine-like CSP device combines the advantages of both the CSP device and the tree-like structure. It has the advantages of low cost, high efficiency, and small footprint, which will solve the problem. This will be a useful attempt to solve the problem of urban solar energy utilization and give new ideas to solve the problem.

With the development of Internet of Things technology, smart homes are increasingly entering the lives of the people. More and more families have put forward ironing, drying, disinfection and intelligent requirements for household wardrobes. However, most household wardrobes currently only have storage functions, which cannot meet people’s needs. Based on the above background, the project team designed a home smart integrated wardrobe. The household intelligent integrated wardrobe can be applied to most families. It has the characteristics of low price, rich functions, and convenient use. The home intelligent integrated wardrobe is conducive to improving people’s living standards and has good application prospects.

Our previous work has established that the dislocation nucleation during the onset of plasticity, the so-called pop-in, in face-centered cubic single-phased high-entropy alloy FeCoCrMnNi is controlled by vacancy defects. This implies that the tip radius would affect the pop in behavior as the number of vacancy, the available sites for dislocation nucleation, within the stressed volume is proportional to radius. To verify this in current work, a wide range of nanoindenter tips with radius across from 200 to 2013 nm were used. It was found that when tip radius is smaller than 638 nm, the pop-in or displacement burst size increases linearly with it, and that when tip radius is larger than 638 nm, the pop—in size became essentially constant. These experimental findings confirm the effect of tip radius on pop-in behavior. A theoretical model based on image force has been developed to rationalize the above observations.

As China’s running enters an aging society, the number of people over the age of 60 is growing rapidly, and the number of “empty-nesters” living alone and widowed is growing at an unprecedented rate. The elderly living alone are the vulnerable groups of the elderly, their own control of the environment and the ability to cope with sudden situations, and no one to take care of, it is easy to accident. Therefore, to create a peaceful, peaceful, happy old age, so that they live in peace and security, happy to spend every day, is a major task we have to take on. Based on the above background, the team members studied and designed a new type of power-assisting device- multi-functional indoor power-assisted chair. The device has the characteristics of light body, clever structure and low cost, including two function modules, auxiliary sitting and auxiliary walking. The coordination and cooperation between the various agencies effectively prevents the accident when the elderly are alone at home, which has high practical value and promotion value.

With the development of China’s economy and the continuous deepening of urbanization, the number of urban private cars has increased dramatically [1]. However, the planning of the community construction was relatively backward at the beginning, this has resulted in many residential areas, especially the old-fashioned ones. The problem of difficult parking is becoming increasingly prominent. Therefore, it is very necessary to design a parking device that can effectively use the existing space and create more parking spaces. In addition, efforts are made to reduce the manufacturing cost of the device, save energy for product operation, avoid complicated maintenance of the device, and reduce potential safety hazards during use. The project team designed a side parking device based on the automatic driving force of the car. The device includes a vehicle-carrying walking module and a motion module. The vehicle-carrying walking module is composed of a laterally-movable vehicle-carrying platform device and a safety baffle mechanism, which realizes the lateral movement of the car parking and prevents accidents during the car parking process. The motion module is composed of a cross-cut telescopic mechanism, a transmission mechanism, a driving mechanism, and a ratchet and pawl mechanism, which realizes the functions of parking the car in the warehouse and preventing the car body from slipping. After many discussions, the members of this project team have fully studied the problems of the existing parking devices and the parking difficulties faced by the old-style residential quarters, the project team decided to start from two aspects: first, to overcome Insufficient; then, to meet the actual needs of parking in the community [3].

Mimicking natural fibrinolytic mechanisms that covalently bind lysine-ligands (free ε-amino and carboxylic groups) onto biomaterial surfaces is an attractive strategy to prevent clot formation on blood contact materials. However, the modification process is typically complicated and limited due to the diversity of biomaterials. Herein, we describe a simple, substrate-independent protocol to prepare a lysine-ligand functionalized layer on biomaterial surfaces. This approach is based on the adsorption and cross-linking of aldehyde-functionalized poly(N-(2,2-dimethoxyethyl)methacrylamide) (APDMEA) and amino-functionalized polymethacryloyl-l-lysine (APMLys) on a variety of substrates, such as polyurethane (PU), polydimethylsiloxane (PDMS), polyvinylchloride (PVC), stainless steel (SS) and cellulose acetate (CA). The lysine-ligand functionalized layer on substrates highly enhanced the specific adsorption of plasminogen from plasma and showed good chemical stability and excellent biocompatibility with L929 cells using the MTT assay. Moreover, for example, after the adsorbed plasminogen was activated and converted into plasmin, the fibrinolytic functionalization of CA was demonstrated using a modified plasma recalcification assay. Collectively, considering the advantages of simplicity, environmental friendliness and substrate-independence, the present study might therefore represent a general approach for the construction of a biointerface with fibrinolytic activity.

The microstructure of the nickel-based single-crystal superalloy DD6 after tensile deformation has been studied by transmission electron microscopy (TEM) with an energy-dispersive X-ray spectroscopy (EDS). The samples were strained to fracture at room temperature, 650 °C, 850 °C and 1020 °C along the [001] orientation. The results indicate that the yield strength at 650 °C is superior to that at room temperature (20 °C), 850 °C and 1020 °C, but low ductility was observed at 650 °C. It is demonstrated that the intermediate temperature brittleness (ITB) behavior was caused by the change of the deformation mechanism at intermediate temperature. At high temperature, the γ′ precipitates coarsening directionally along the direction perpendicular to the stress axis. This can be attributed to the directional diffusion of the chemical elements. Keywords: Nickel-based single-crystal superalloy, Microstructure, Deformation mechanism, Directional coarsening

A simple and versatile method for the preparation of surfaces to control bacterial adhesion is described. Substrates were first treated with two catechol-based polymerization initiators, one for thermal initiation and one for visible-light photoinitiation. Graft polymerization in sequence of dimethylaminoethyl methacrylate (DMAEMA) and 3-acrylamidebenzene boronic acid (BA) from the surface-bound initiators to form mixed polymer brushes on the substrate was then carried out. The PDMAEMA grafts were thermally initiated and the PBA grafts were visible-light-photoinitiated. Gold, poly(vinyl chloride) (PVC), and poly(dimethylsiloxane) (PDMS) were used as model substrates. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), and ellipsometry analysis confirmed the successful grafting of PDMAEMA/PBA mixed brushes. We demonstrated that the resulting surfaces showed charge-reversal properties in response to change of pH. The transition in surface charge at a specific pH allowed the surface to be reversibly switched from bacteria-adhesive to bacteria-resistant. At pH 4.5, below the isoelectric points (IEP, pH 5.3) of the mixed brushes, the surfaces are positively charged and the negatively charged Gram-positive S. aureus adheres at high density (2.6 × 10(6) cells/cm(2)) due to attractive electrostatic interactions. Subsequently, upon increasing the pH to 9.0 to give negatively charged polymer brush surface, ∼90% of the adherent bacteria are released from the surface, presumably due to repulsive electrostatic interactions. This approach provides a simple method for the preparation of surfaces on which bacterial adhesion can be controlled and is applicable to a wide variety of substrates.

Tensile behavior of the nickel-base single-crystal superalloy DD6 was studied from room temperature to 1020 °C. The plate specimens were along [001] orientation parallel to the loading axis in tension. The microstructures on the surface and fracture morphology were investigated after tensile test to rupture by scanning electron microscopy (SEM). The results of the present investigation indicate that the yield strength at 650 °C is superior to that at room temperature, 850 °C and 1020 °C. Low ductility and serrated flow in stress–strain curves were also observed at 650 °C. The microstructures on the surface of the plate specimens and fracture morphology observation indicated that localized slip which resulted in glide plane decohesion caused the low ductility of DD6 alloy.

Tailoring the surface properties of poly(dimethylsiloxane) (PDMS) is essential for the advancement of its applications. However, the modification process is usually complicated and limited due to the chemical inertness of the surfaces of PDMS. Here, we report for the first time, a facile and versatile method for the functional surface modification of PDMS via visible light-induced grafting polymerization at room temperature. This modification is readily achieved in two steps: (1) covalently integrating alkyl bromine into the PDMS networks using a simple mixing procedure and (2) visible light-induced surface grafting polymerization using Mn2(CO)10. We have demonstrated that the PDMS surface can be functionalized with a wide variety of polymers via covalent grafting, such as poly(trifluoroethyl methacrylate) (PTFEMA), poly(N-isopropylacrylamide) (PNIPAAm), poly(acrylic acid) (PAA) and poly(vinyl acetate) (PVAc). As an example, after the grafted PVAc was transformed into its hydrophilic analogue poly(vinyl alcohol) (PVA), anti-biofouling functionalization of PDMS was obtained. The anti-biofouling properties of the functionalized PDMS were demonstrated using cell adhesion and bacterial adhesion tests. Moreover, the grafting kinetics of PVAc showed that this process was fast and efficient.

Circulating tumor cells (CTCs) exist in extraordinarily low numbers in the blood of patients with solid tumors, and thus the discovery of a more effective, economical and specific way to capture tumor cells is essential and still remains a tremendous challenge. In this work, the glycopolymer, poly(N-acryloyl glucosamine) (PAGA), and TD05 aptamers were combined on silicon nanowire arrays (SiNWAs) to capture Ramos cells through SET-LRP and click chemistry for the first time. The polymerizations showed controllable living features using 2-hydroxyethyl α-bromoisobutyrate (HEBiB) as a sacrificial initiator. In a serum-containing environment, PAGA-modified surfaces could catch small amounts of Ramos cells. Furthermore, the number of captured specific Ramos cells increased extensively compared with the control after the introduction of the aptamer molecule TD05 onto the PAGA-modified surface. A few non-specific Baf3 cells were captured on the surfaces prepared. The results revealed the synergistic effect generated by combining a glycopolymer and aptamer, which could achieve multivalency-enhanced effective and specific cancer cell capturing, thus suggesting that this can be a promising approach for cancer detection.

Liquid-based mobile interfaces, in which liquids are being utilized as structural long-term components, have shown their multifunctionality in materials science, such as the hydration layer of polyelectrolyte brushes used for artificial implants, stabilized lubricants for antibiofouling, anti-icing, self-cleaning, optical control, and so forth. However, these currently available systems do not usually show a response to environmental stimuli. Here, we describe a strategy for preparing thermoresponsive mobile interfaces made from novel silicone-based lubricants that display lower critical solution temperature and demonstrate their capabilities on controlling in situ water wetting and dewetting, thermo-gating penetration, and optical properties. These properties allow the mobile films to form a kind of erasable recording platforms. We foresee diverse applications in liquid transport, wetting and adhesion control, and transport switching.

The major bottleneck for gene delivery lies in the lack of safe and efficient gene vectors and delivery systems. In order to develop a much safer and efficient transfection system, a novel strategy of combining traditional Ca(2+)-dependent transfection with cationic polymer poly(N,N-dimethylamino)ethyl methacrylate (PDMAEMA) modified silicon nanowire arrays (SiNWAs) was proposed in this work. Detailed studies were carried out on the effects of the PDMAEMA polymerization time, the Ca(2+) concentration, and the incubation time of Ca(2+)@DNA complex with PDMAEMA-modified SiNWAs (SN-PDM) on the gene transfection in the cells. The results demonstrated that the transfection efficiency of SN-PDM assisted traditional Ca(2+)-dependent transfection was significantly enhanced compared to those without any surface assistance, and SN-PDM with polymerization time 24 h exhibited the highest efficiency. Moreover, the optimal transfection efficiency was found at the system of a complex containing Ca(2+) (100 mM) and plasmid DNA (pDNA) incubated on SN-PDM for 20 min. Compared with unmodified SiNWAs, SN-PDM has little cytotoxicity and can improve cell attachment. All of these results demonstrated that SN-PDM could significantly enhance Ca(2+)-dependent transfection; this process depends on the amino groups' density of PDMAEMA on the surface, the Ca(2+) concentration, and the available Ca(2+)@DNA complex. Our study provides a potential novel and excellent means of gene delivery for therapeutic applications.

Rapid prototyping (RP), especially metal direct rapid prototyping, brings engineers a new model to fabricate parts more difficultly than conventional machining. Furthermore, the surface quality and the dimensional accuracy of the parts manufactured using the simplex metal direct prototyping or tooling approach are even lower than that of the conventionally machined parts. To overcome these deficiencies, this paper presents a new metal direct RP approach, called hybrid plasma deposition and milling (HPDM) using plasma deposition as an additive and conventional milling as a subtractive technique, which synthesizes the advantages of both processes. Compared with other metal-deposition ways, such as laser or electron beam deposition processes, the plasma deposition used in the current HPDM is the most economical one. Simultaneously, the precision of the manufactured parts is ensured by the compounding CNC process which assists to remove the staircase caused by the layered manufacturing principle and the allowance of the near-net shape deposited by plasma deposition. The initial results of the process development and the characteristics of the parts fabricated by this process are reported in this paper. Using a set of optimized process parameters obtained in this study, a group of metal parts, such as metal hollow vases, were trial-manufactured. The surface roughness R z was obtained 2.32 μm and the dimensional accuracy was controlled within ±0.05% of the metal part. With these results obtained, the microstructure was then examined to prove the applicability of the HPDM process to direct fabrication of metallic prototypes and tools.

PurposeThe purpose of this paper is to develop a novel hybrid plasma deposition and milling (HPDM). For solving the bottleneck problem of low‐surface quality in existing direct rapid metal prototyping technologies.Design/methodology/approachHPDM uses plasma deposition as an additive and conventional milling as subtractive technique, which synthesizes the advantages of both processes. Compared to other laser or electron beam deposition processes, plasma deposition used in HPDM is one of the most economic ways of depositing metals, CNC assisted to ensure the precision of the manufactured parts simultaneity.FindingsThis paper focus on the experimental investigation to find the basic process characteristics, the optimization of the process parameters such as transferred arc current, workpiece's speed, powder flow rate and feed per tooth using a statistical approach. Some metal parts, for instance, metal torsional vane, are then trial‐manufactured.Research limitations/implicationsThe manufacturing cycle of HPDM is longer than simplex direct metal rapid prototyping, and the surface accuracy should be further investigated.Practical implicationsHPDM is a very useful and effective method to manufacture metal parts with fine surface state directly.Originality/valueThis paper describes a novel process and manufacturing system for fabrication metal prototyping direct, which can improve the inside and outside quality of the metal rapid prototypes.

The tantalum tungsten alloys, Ta-2.5 W and Ta-10 W, were treated with isothermal ion nitriding and two-stage ion nitriding experiments to obtain a nitride layer. After the treatment, the hardness of both alloys has been remarkably improved, which can be attributed to the formation of nitride phase θ-TaN in the surface layer according to the XRD pattern. Comparing with isothermal ion nitriding, the two-stage ion nitriding experiment achieved greater microhardness and thickness of the nitride layer. In addition, T-2.5 W alloy showed a greater layer thickness and microhardness than Ta-10 W alloy with the same treatment, which indicates that the nitriding process decreases with the increase of tungsten content.

To overcome the problem caused by the lability of the Au-S bond, we demonstrate the first use of Mn2(CO)10 for visible-light-induced surface grafting polymerization on Au surfaces in this paper. The visible-light-induced surface grafting of poly(N-isopropylacrylamide) (PNIPAAm) has the features of a "controlled" polymerization, which is characterized by a linear relationship between the thickness of the grafting layer and the monomer concentration. Ellipsometry indicated the formation of PNIPAAm films of up to ∼200 nm in thickness after only 10 min of polymerization at room temperature, demonstrating that this is a very fast process in comparison with traditional grafting polymerization techniques. Moreover, to demonstrate the potential applications of our approach, different substrates grafted by PNIPAAm and the covalent immobilization of a range of polymers on Au surfaces were also demonstrated. Considering the advantages of simplicity, efficiency, and mild reaction conditions as well as the ability of catecholic derivatives to bind to a large variety of substrates, this visible-light-induced grafting method is expected to be useful in designing functional interfaces.