检索结果-南通市图书馆

Production of Functional Materials Derived from Regenerated Silk Fibroin by Utilizing 3D Printing and Biomimetic Enzyme-induced Mineralization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第3期42卷 299-310,I0005页

作者： ni Chen Fei-Yu Luo Gong-Wen Yang Jin-Rong Yao Xin Chen Zheng-Zhong Shao State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique,integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase(ALP), was developed. Initially,a pre-cured hydrogel of regenerated silk fibroin(RSF) with a small quantity of hydroxypropyl cellulose(HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate(Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization ***, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures.

关键词： Silk protein Alkaline phosphatase Extrusion-based printing Biomineralization

维普期刊数据库

Sodium butyrate alleviates fructose-induced non-alcoholic fatty liver disease by remodeling gut microbiota to promoteγ-amino butyric acid production

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2024年第2期13卷 961-971页

作者： Qu Chen Lei Wu Aijia Zhang Chen Wu Liuping Cai Yingping Xiao Yingdong ni Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture and Rural AffairsNanjing Agricultural UniversityNanjing 210095China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Institute of Agro-product Safety and NutritionZhejiang Academy of Agricultural SciencesHangzhou 310022China

Sodium butyrate(NaB)can regulate lipid metabolism and inhibit hepatic *** study aimed to investigate whether NaB can alleviate fructose-induced hepat ic steatosis via remodeling the gut microbiota and evaluate the anti-fatty liver *** results showed that NaB and NaB-remodeled gut microbiota significantly alleviated fructose-induced hepatic steatosis and increased plasma uric acid and fructose ***,both NaB and NaB-remodeled gut microbiota increased the abundance of Lactobacillus and altered the levels of plasma amino acids(upregulating gamma-amino butyric acid(GABA)and downregulating L-glutamic acid and L-arginine)in fructose-exposed *** correlation analysis showed that GABA levels positively correlated with Lactobacillus abundance,and increased GABA levels might promote the reduction of the hepatic triglyceride *** studies confirmed that GABA significantly reduced lipid deposition in mouse hepatocytes induced via fructose pretreatment in *** findings suggested that NaB could ameliorate fructose-induced hepatic steatosis by regulating gut microbiota.

关键词： Butyrate Fructose Gut microbiota Hepatic steatosis

维普期刊数据库

Starting materials, processes and characteristics of bio-based foams: A review

在线全文

学校读者我要写书评

暂无评论

Journal of Bioresources and Bioproducts 2024年第2期9卷 160-173页

作者： Xiaohan Wang Jinwon Jang Yanqun Su Jingang Liu Hongjie Zhang Zhibin He Yonghao ni National Engineering Laboratory for Pulp and Paper China National Pulp and Paper Research Institute Co.Ltd.Beijing 100102China Limerick Pulp and Paper Centre and Department of Chemical Engineering University of New BrunswickNew Brunswick E3B 5A3Canada

Biofoam products have attracted considerable attention lately because there is a growing demand for green/sustainable *** this end,various biobased foams have either been developed or are currently in development,e.g.,bio-based polyurethanes(PUs),polylactic acid(PLA),starch,and polyhydroxyalkanotates(PHAs).Indeed,significant progress has been made;however,chal-lenges still persist,for example,biobased foam products have poor processability,inferior com-patibility,thermal and strength *** this review,we focus on five biofoam products:namely bio-based PUs,PLA,starch,PHAs,and cellulose biofoam products,along with their prop-erties and performance,as well as their manufacturing *** efforts are still needed to unlock the full potential of these bio-based products and meet the goal of complementing and gradually replacing some of their fossil-based ***,the challenges,as well as arising opportunities of future research directions are discussed.

关键词： Biofoam Bio-based polyurethanes Polylactic acid Polyhydroxyalkanotate Starch Cellulose Manufacturing process

Durable Design of Superhydrophobic Coatings with TiO_(2)Particles and Al_(2)O_(3)Whiskers for the Enhanced Anti-icing Performance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第3期21卷 1360-1374页

作者： Weilan Liu Kunlong Li Yizhou Shen Huanyu Zhao Yaru ni Zeyu Cai Lingfeng Zhao Zhen Wang Institute of Advanced Materials(IAM) School of Materials Science and EngineeringNanjing Tech UniversityNanjing211816China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China Aviation Industry Aerodynamics Research Institute of China Shenyang110000China

Superhydrophobic coatings with high non-wetting properties are widely applied in anti-icing ***,the micro-nanostructures on the surfaces of superhydrophobic coatings are fragile under external forces,resulting in reduced ***,mechanical strength and durability play a crucial role in the utilization of superhydrophobic *** this study,we employed a two-step spraying method to fabricate superhydrophobic FEVE-based coatings with exceptional mechanical durability,utilizing fluorinated TiO_(2)nanoparticles and fluorinated Al_(2)O_(3)microwhiskers as the *** composite coating exhibited commendable non-wetting properties,displaying a contact angle of 164.84°and a sliding angle of 4.3°.On this basis,the stability of coatings was significantly improved due to the interlocking effect of Al_(2)O_(3)*** 500 tape peeling cycles,500 sandpaper abrasion tests,and 50 kg falling sand impact tests,the coatings retained superhydrophobicity,exhibiting excellent durability and application ***,the ice adhesion strength on the coatings was measured at only 65.4 kPa,while the icing delay time reached 271.8 s at-15℃.In addition,throughout 500 freezing/melting cycles,statistical analysis revealed that the superhydrophobic coatings exhibited a freezing initiation temperature as low as-17.25℃.

关键词： Superhydrophobic coatings Anti-icing Mechanical durability

A Review of the Latest Control Strategies for Mosquito-Borne Diseases

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China CDC weekly 2024年第33期6卷 852-856页

作者： Jing ni Jinna Wang Chunfu Fang Wenrong Zhang Zhenyu Gong School of Public Health Hangzhou Medical CollegeHangzhou CityZhejiang ProvinceChina Department of Communicable Disease Control and Prevention Zhejiang Provincial Center for Disease Control and PreventionHangzhou CityZhejiang ProvinceChina Quzhou Center for Disease Control and Prevention Quzhou CityZhejiang ProvinceChina

Mosquito-borne diseases are persistent and potentially severe posing a threat to global pandemic *** risk of mosquito-borne virus transmission is rapidly increasing due to the unprecedented spread of viruses such as dengue and chikungunya,the disruption of global mosquito-borne disease control efforts following the emergence of coronavirus diseases 2019(COVID-19)in 2019,global warming,and human *** address this global challenge,various innovative mosquito control technologies are being developed *** paper summarizes the latest advances in mosquito vector control,focusing on China’s latest mosquito control strategies,to provide insights into implementing novel mosquito-borne disease control measures.

关键词： diseases warming insight

Development of the electric automatic steering system for agricultural vehicles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2024年第1期17卷 209-214页

作者： Guangshun An Chong Yu Juan Du Xiang Yin Youliang ni Chengqian Jin School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina Nanjing Research Institute for Agricultural Mechanization of Ministry of Agriculture and Rural Affairs Nanjing 210014China

Automatic guidance of agricultural vehicles requires automatic execution of operation commands received from the navigation controller by using electronically controlled mechanisms for wheel steering,speed changing and work *** steering contributes as a prerequisite technique in automatic and semi-automatic agricultural *** research aimed to develop an electric automatic steering system that was compact in its structure and integrated into original steering mechanism in a simply and convenient way for aftermarket modification.A brushless motor and reducer assembly was utilized to provide an adequate steering torque instead of manual maneuver.A rapid assembling approach was proposed by passing the steering shaft through the hollow output shaft.A digital proportional-integral-differential(PID)algorithm was implemented to calculate the rotation speeds and directions by comparing the desired angle and the actual angle,which was implemented in a printed circuit board with a microcontroller unit(MCU)and interface *** unmanned wheeled tractor was applied as test platform to integrate the newly developed electric automatic steering *** were conducted to evaluate its performance in terms of stability and *** autonomous navigation system guided the tractor along target paths in the field by sending steering commands to the electric automatic steering *** results show that the steering angle error was less than 0.81°when desired steering angle was less than 10°.The lateral error difference was no more than 4.76 cm when repeating following the same target path,which indicated that the electric automatic steering system responded accurately and robustly to steering commands.

关键词： automatic steering automatic navigation agricultural vehicles

Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3047-3062页

作者： Jianhua Yan Xiansen Xing Zhihai Li Weida ni Liuyuan Zhao Chun Zhu Yuanyuan He School of Earth Sciences and Engineering Hohai UniversityNanjing210098China POWERCHINA Huadong Engineering Corporation Limited Hangzhou311122China Zhejiang Huadong Construction Corporation Limited Hangzhou310004China The Seventh Geological Brigade of Hubei Geological Bureau Yichang443000China

In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation *** this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable *** study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks *** proposed approach was applied to a granite mine in ***,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit ***,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each ***,a bench face angle was determined commensurate with an acceptable risk level of *** simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.

关键词： Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope

Molecule aging induced by electron attacking

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第6期93卷 519-525,I0013页

作者： Ping Song Yining Dong Xue Gong Mingbo Ruan Baoxin ni Xuanhao Mei Kun Jiang Weilin Xu State Key Laboratory of Electroanalytical Chemistry and Jilin Province Key Laboratory of Low Carbon Chemical Power Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina School of Applied Chemistry and Engineering University of Science and Technology of Chin1Hefei 230026AnhuiChina Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryFudan UniversityShanghai 200438China

Here we propose a new concept of"molecule aging":with some special treatment,a molecule could be"aged"by losing some unknown tiny particles or pieces from atoms in the molecule,Such"aging"or loss of unknown tiny particles does not change apparently its molecular structure or chemical composition,but some physicochemical properties could be changed *** further confirm such"molecule aging"via a long-term electron attacking to age water(H_(2)O)*** IR spectra show no structural difference between the fresh water and the aged one,while the NMR spectra show that the electron attacking can decrease the size of water *** facts indicate that the electron attacking indeed can"affect"the structure of water molecule slightly but without damaging to its basic molecule *** exploration reveals that the hydrogen evolution reaction(HER)activity of the aged water molecule is lower than the fresh water on the same Pt/C *** density functional theory calculations indicate that the shortened O-H bond in H_(2)O indeed can present lower HER activity,so the observed size decrease of water clusters from NMR probably could be attributed to the shortening of O-H bond in water *** results indicate significantly that the molecule aging can produce materials with new functions for new possible applications.

关键词： Aging of molecules Electron attacking Full width at half maxima Hydrogen evolution reaction

维普期刊数据库

Lift system optimization for hover-capable flapping wing micro air vehicle

在线全文

学校读者我要写书评

暂无评论

Frontiers of Mechanical Engineering 2024年第3期19卷 61-75页

作者： Shengjie XIAO Yongqi SHI Zemin WANG Zhe ni Yuhang ZHENG Huichao DENG Xilun DING Department of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China

A key challenge is using bionic mechanisms to enhance aerodynamic performance of hover-capable flapping wing micro air vehicle(FWMAV).This paper presented a new lift system with high lift and aerodynamic efficiency,which use a hummingbird as a bionic *** new lift system is able to effectively utilize the high lift mechanism of hummingbirds,and this study innovatively utilizes elastic energy storage elements and installs them at the wing root to help improve aerodynamic performance.A flapping angle of 154°is achieved through the optimization of the flapping mechanism *** optimized wing shape and parameters are obtained through experimental studies on the ***,the max net lift generated is 17.6%of the flapping wing vehicle’s ***,energy is stored and released periodically during the flapping cycle,by imitating the musculoskeletal system at the wing roots of hummingbirds,thereby improving the energy utilization rate of the FWMAV and reducing power consumption by 4.5%under the same ***,strength verification and modal analyses are conducted on the flapping mechanism,and the weight of the flapping mechanism is reduced through the analysis and testing of different *** results show that the lift system can generate a stable lift of 31.98 g with a wingspan of 175 mm,while the lift system weighs only 10.5 g,providing aerodynamic conditions suitable for high maneuverability flight of FWMAVs.

关键词： lift optimization flapping wing elastic energy hovering flapping mechanism