Abstract:The hypoxia-responsive 6-(2-nitroimidazole) hexanoic acid (NIHA) was synthesized using 2-nitroazole and 6-bromohexanoic acid ethyl ester. The amphiphilic chitosan-g-6-(2-nitroimidazole) hexanamide derivatives (CS-NID) with substitution degrees of 3.9%, 6.3% and 8.9% were obtained by grafting NIHA onto the chitosan macromolecule. The structure of CS-NID conjugates was confirmed by 1H NMR, UV and FT-IR. The micelles were obtained by the self-assembly of CS-NID in aqueous solution and characterized by DLS, Zeta potential and UV. The average size of CS-NID micelles was about 165-190 nm and decreased with increasing the substitution degrees of NIHA. The CS-NID micelles exhibited excellent storage stability, mucoadhesion and hypoxia responsiveness. Doxorubicin (DOX) was encapsulated in micelles by the hydrophobic interaction, and the maximum drug loading content (DLC) and loading efficiency (DLE) of CS-NID micelles were 13.3% and 44.3% respectively. In vitro drug release showed that DOX was released from CS-NID micelles with a distinctly hypoxia-responsive manner. Only 42% of loaded Dox was released from the CS-NID micelles under normoxic conditions over 24h. Notably, about 65% of loaded DOX was released from the CS-NID micelles under hypoxic conditions in 2h, and over 92% DOX was released within 24 h under hypoxic conditions.

Abstract:Aerogel materials have numerous interesting features, including a high specific surface area, high porosity, low density, and low thermal conductivity, and are regarded as one of the top ten novel materials of the twenty-first century. However, due to the mechanical characteristic’s limitations of typical aerogels, it is difficult to fabricate aerogels with complicated shape structure by post-processing, limiting their practical applicability. Therefore, 3D printing technology which can customize the shape of material without complex post-treatment is predicted to become an innovative manufacturing technology that overcomes these constraints in the applications of aerogel materials. This review discusses the development of 3D printing aerogels from printing methods and material classification; summarizes the unique applications of 3D printed aerogel materials in flame retardant thermal insulation, dielectric, and tissue engineering. The future development of 3D printed aerogel materials is prospected, and it is proposed to broaden the material system of 3D aerogel materials, develop 3D printing technology more suitable for aerogel printing, enhance the printing accuracy and speed, and investigate the influence of the controllable pore structure of 3D printing aerogels on its performance. The development of 3D printing aerogel materials is expected to promote the rapid development of aerogel materials. Key words: 3D printing; aerogel; extrusion; photo-curing; development

Abstract:The cores of fire warning system are new sensing materials. MXene and its derivatives have high electronic conductivity, large specific surface area, and unique temperature and gas sensitivity, which can realize fast and reliable warning of early fire, showing wide practicability in fire early warning sensors. Herein, the early warning mechanism and the progress of temperature-sensitive MXene-based fire alarms have been reviewed including paper type and coating layer type sensors. Then the early warning mechanism of gas-sensitive MXene-based fire alarms and the development status of MXene and its derivatives in detecting of NH3, NO2, CO, and other gases have also been reviewed. The research progress of MXene-based fire warning sensors in high-performance and multifunctional fire warning system is summarized emphatically, and the future development trend of MXene-based fire warning sensors is forecasted. It is suggested that the future MXene-based fire warning sensors should be optimized through developing new MXene-based sensitive materials to reduce their response time, improve the rapidity and accuracy, and consider giving the device self-healing, electromagnetic shielding, hydrophobic and other multifunctional features. Meanwhile, linking them with the Internet of Things can achieve intelligent fire protection, and further make them more suitable to be used in complex environment and practical engineering field in the future.

Abstract:Alkyd resin has many advantages, such as fullness, brightness, good adhesion, biodegradability and so on. It is widely used in vehicle, ship, paint and coating industries. However, the durability of alkyd resin coating is poor, and it is vulnerable to external friction stress in the process of use, which makes the protective effect of the coating ineffective. Therefore, enhance the mechanical properties of alkyd resin coating so that it is not easy to be damaged in the process of use is still the focus of attention. It is very important to improve the wear resistance of alkyd resin coating. On the basis of consulting a large number of literatures, this paper summarizes the synthesis methods of waterborne alkyd resin, the factors affecting the wear resistance of waterborne alkyd resin and the abrasion resistance modification of waterborne alkyd resin. At present, the main methods to improve the abrasion resistance of alkyd resin coating are to improve the synthesis process and modify the alkyd resin with functional materials, and improve the properties of alkyd resin from the aspects of coating strength, hardness and toughness. In this paper, the development trend of abrasion resistance waterborne alkyd resin in the future is prospected in order to provide reference and guidance for relevant workers. The author analyzes that the progress of abrasion resistance alkyd resin in the future mainly focuses on the discovery of biological raw materials, the application of new materials, the application scope of alkyd resin and so on.

Abstract:Solar interface evaporation (SIE) is a process of concentrating solar energy at the "air water" interface for heating, efficient gas production and seawater desalination. This method can effectively solve the problems of shortage of fresh water resources and low energy conversion efficiency. With the rapid development of photothermal materials and integrated systems, the function of interface evaporator is continuously optimized, which promotes the technical breakthrough of this method in the fields of water treatment, steam sterilization, enrichment of scarce resources and cogeneration power generation. Based on the previous research, combined with the latest research progress of SIE collaborative power generation, this paper combs the mechanism of SIE collaborative power generation, analyzes the design points of SIE collaborative power generation device, summarizes the practical application status of SIE collaborative power generation, and looks forward to its future development and challenges.

Abstract:MgCl2 was used as the crystal surface regulator to regulate the selective growth of (001) crystal surface of MH by hydrothermal method, and the effects of concentration of crystal surface regulator, reaction temperature and reaction time on the dissolution and crystallization of MH particles were investigated. Compared with the raw material, the XRD peak intensity of the regulated products I001/I101 and I001/I110 increased by 214.30% and 307.45%, respectively, and that of the 100-ton pilot scale test products I001/I101 and I001/I110 increased by 84.08% and 112.99%, respectively. compared with the raw material. The morphology and structure of MH products were characterized by XRD, FE-SEM, TEM, FTIR, and particle size analyzer, and the regulation mechanism was investigated. The results show that MgCl2 can promote the (001) crystal face selective growth of MH in the hydrothermal system. On the one hand, MgCl2 as a strong acid and weak base salt lowers the pH of the system, while Cl－ can cause further accelerated dissolution of MH through charge neutralization effect. On the other hand, the Cl－ provided by MgCl2 acts on the crystallization process of MH and intensifies the growth of (001) crystalline facets by promoting the growth of MH edges. In this paper, we further investigated the effects of crystalline surface modifier concentration, reaction temperature and reaction time on the dissolution and crystallization of MH particles.

Abstract:The electron donating properties of benzidine units were enhanced by substituent modification, then by copolymerizing then with benzaldehyde units a group of conjugated polymers with donor acceptor structure were synthesized based on the simple structure design. The structures of the monomers and polymers were characterized by H NMR, FT-IR and XRD, which showed that the target products were successfully prepared. The photoelectric and electrochemical properties of the copolymers were tested by UV-vis, UV-vis-DRS, cyclic voltammetry, chronopotentiometry, AC impedance and cyclic performance tests. The results show that the conjugated polymer P3 prepared by introducing methoxyl group has higher conjugation degree and better crystallinity, and its optical band gap E_g^opt is 2.09 eV. This sample has higher HOMO and lower LUMO values, which are -5.15 eV and -3.06 eV respectively, showing better redox performance, and correspondingly also showing better electrochemical capacitance characteristics. At 0.3 A/g, the first discharge specific capacitance of P3 tested by constant current charge and discharge reaches 1030 F/g, and remains at 530 F/g after 700 cycles.

Abstract:Passive daytime radiative cooling (PDRC) technology has received a lot of attention because it does not require external energy and is green and pollution-free. A polydimethylsiloxane (PDMS) -based superhydrophobic radiative cooling film was fabricated by casting and drying of PDMS/ZrO2 dispersion, followed by spray-coating of PDMS/SiO2 dispersion. The ZrO2 particle size in the casting solution and the SiO2 dosage in the spraying solution were optimized to made the film have self-cleaning property with a CA of 156.6 ° ± 2 ° and SA of 0.3 ° ± 0.1 °, the reflectivity of the film in the solar band (0.3-2.5 μm) and the infrared emissivity in the atmospheric window (8-13 μm) reached 95.3% and more than 90%, respectively. The average cooling effect of the film was 9.99 ℃ lower than the ambient temperature under direct sunlight. The self-cleaning property of the film can keep the film free from soil contamination and maintain the cooling performance. Moreover, the film exhibited excellent mechanical properties, friction resistance, chemical stability of superhydrophobicity and cooling performance after immersion in different pH solutions or UV irradiation.

Abstract:The development of active, stable and low-cost non-noble-metal electrocatalysts for water splitting, particularly those that can catalyze both the hydrogen evolution reaction (HER) at the cathode and oxygen evolution reaction (OER) at the anode, is a challenge. CoSe2@NF electrodes were prepared on nickel foam by hydrothermal and solid state process with cobalt nitrate hexahydrate, urea, ammonium fluoride and selenium powder. The structure and performance were characterized by XRD, XPS, SEM and TEM. The OER and HER properties were tested in alkaline solution. The results showed that the bead like structure with rough surface greatly improved the specific surface area and increased the number of effective active sites. CoSe2/NF shows high and stable catalytic activity in both the HER and OER in alkaline solution. At 1.6V cell voltage，the water cell equipped with CoSe2/NF electrodes give a current of 10 mA/cm2. It can operate stably for 100 h with the cell potential of 1.7 V. Consequently, these novel bifunctional electrodes are promising candidates for large-scale water electrolysis.

Abstract:A series of glucosamide quaternary ammonium salt surfactants (CnDGMAPB, where n represents the hydrocarbon chain length of 8, 10, 12, 14 and 16) were successfully synthesized from glucosactone, N, N-dibutyl-1, 3-diaminopropane, and bromoalkane using two-step method of amine ester reaction and quaternary ammonium reaction. The intermediates and products were characterized by FTIR, 1H-NMR and 13C-NMR. The surface activity, wettability, emulsifying, foam and toxicity of the product were studied. The results showed that CnDGMAPB has good surface activity. The critical micelle concentration (cmc) and molecular cross-sectional area (Amin) decreases, the surface activity efficiency (pC20) and saturated adsorption capacity (Гmax) gradually inceased with increasing the carbon chain length. The surface tension (γcmc) value was between 28-32 mN/m. The contact angle between C12DGMAPB/ C16DGMAPB solution and polytetrafluoroethylene membrane (PTFE) was reduced to 47o within the concentration (0.01-5 mmol/L) range. This kind of glycosylamide quaternary ammonium salt had good wetting and emulsifying properties. The foam volume was very low at 5 min, which belongs to the typical low foam product. Both cell toxicity and acute oral toxicity experiment showed that the CnDGMAPB surfactants were low-toxic products. The antibacterial rate of escherichia coli and staphylococcus aureus can reach 100% at the C12DGMAPB concentration of 0.2 g/L, no irritation to skin, and has good antistatic performance.

Abstract:The objectives of this research were to extract and purify two water soluble polysaccharides from Borage leaves, further explore the structural characteristics and evaluate the hypoglycemic, anticancer and immunological activities. Two water-soluble polysaccharides were extracted and purified from Borage leaves by cellulose enzyme assisted extraction (BLP-1) and microwave assisted extraction (BLP-2), respectively. The physicochemical properties of BLP-1 and BLP-2 were investigated and compared. The hypoglycemic activities of BLP-1 and BLP-2 were evaluated by detecting the inhibition rate of α-glucosidase and α-amylase, the anticancer activities were evaluated by detecting the inhibition rate of HepG2, MX-1, and A549 cells, and the immune activities were evaluated by detecting the secretion of the immune factors of RAW246.7 cells. Results showed that BLP-1 and BLP-2 had different sugar, and protein contents. BLP-1 and BLP-2 were consisted of Ara, Gal, Glc, Xyl, and with molecular weights (Mws) of 20.1 and 22.6 kDa, respectively. Thermal gravimetric analysis (TGA) suggested that BLP-2 had more a stable structure than BLP-1. The two polysaccharides have potential for inhibiting α-glucosidase and α-amylase activities, suppressing HepG-2, A549 and MX-1 cancer cells proliferation, and activating macrophage RAW 264.7 cells to secret immune cytokines for mediating cellular immune response. BLP-1 and BLP-2 could be used as a bioactive ingredient in new functional foods and pharmaceutical products,which provided a theoretical basis for further study on the structure-activity relationship.

Abstract:To develop new compounds with high biological activity, a series of novel N-pyridylpyrazole-4-carboxamides containing sulfur moiety were designed and synthesized. The target compounds were identified by 1H NMR, 13C NMR, high-resolution mass spectrum (HRMS) or elemental analysis. The insecticidal activities of new compounds against oriental armyworm (Mythimna separata) were evaluated. The results of bioassays indicated that the title compounds showed moderate activities at the 200mg/L. Moreover, the fungicidal activities in vitro against five fungi at 50 mg/L indicated that some compounds exhibited promising fungicidal activities. Especially, N-[4-chloro-2-methyl-6-(methylcarbamoyl)phenyl]-1-(3-chloropyridin -2-yl)-3- (methylsulfanyl)-1H-pyrazole-4-carboxamide If and N-[4-chloro-2-(cyclopropylcarbamoyl)-6-methylphenyl] -1-(3-chloropyridin-2-yl)-3-(methylsulfanyl)-1H-pyrazole-4-carboxamide Ig displayed a good fungicidal activity against Alternaria solani, the inhibitory rate were 65.2% and 67.1%, respectively, which was higher than the positive control compound chlorothalonil.

Abstract:To solve the problem that it is difficult to recycle the metal-organic framework material ZIF-8 in aqueous solution, sodium alginate (SA) was used as the base material, the mixed sol of SA and graphene oxide (GO) was dropped into Ca2+ solution by direct drop addition, crosslinking formed SA/GO gel substrate, and then in-situ growth of ZIF-8 on SA/GO substrate. And SA/GO/ZIF-8 composite adsorbent was prepared to remove tetracycline hydrochloride (TC) from environmental wastewater. XRD, TEM and SEM results showed that ZIF-8 grew uniformly on SA/GO gel substrate, and the calculated load rate of ZIF-8 is as high as 34.21%. When the temperature is 25 ℃, pH=7 and TC concentration is 50 mg/L, the equilibrium adsorption capacity of 30 mg SA/GO/ZIF-8 composite adsorbent for TC can reach 125.37 mg/g. Adsorption kinetics and isotherm results showed that the adsorption process of SA/GO/ZIF-8 on TC was controlled by the chemical active site, and it was a uniform monolayer adsorption at the active site. Furthermore, after 6 cycles of adsorption, the removal rate of TC by SA/GO/ZIF-8 composite adsorbent is still above 85%. The method of easy separation and high loading of ZIFs makes SA/GO/ZIF-8 composite sorbents ideal for antibiotic removal from wastewater.

Abstract:Using acrylamide (AM), acrylic acid (AA), and glutamic acid chelating agent (CH-3) with double bonds as raw materials, a new type of polyacrylamide polymer p(AM/AA/CH-3) was synthesized by inverse emulsion polymerization. The functional groups were successfully introduced into the polymerization reaction by infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. Scanning electron microscope test results show that the polymer and salt ions form a more compact and regular structure. Laser particle size distribution analyzer test showed that the polymer particle size distribution was concentrated and uniform. The rheological test results show that the polymer has a stress loop in brine. The p(AM/AA/CH-3) aqueous solution with a mass fraction of 0.8% showed good temperature resistance. In 20000 mg/L NaCl and CaCl2 solutions, the viscosity of p(AM/AA/CH-3) with a mass fraction of 0.8% after shearing at 140 ℃ for 1 h was 70.53 mPa·s and 53.84 mPa·s, respectively. The system has good temperature resistance and shear resistance. The polymer behaves as an elastomer in the salt solution. Since the intermolecular force of the polymer is greater than the intramolecular force, a denser and more complex spatial network structure is formed, and the elasticity of the polymer increases.