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    题名 作者 年代 出处 被引量
1美国油气管道维抢修应急响应程序显示文摘美国油气管道维抢修应急响应体系完备,主要体现在由联邦、州、地方政府机构、油气管道行业、公共安全以及其他组织机构的协调运行管理。介绍了建立管道维抢修应急响应程序遵循的主要法律法规和与之相关的立法机构。基于国家事故管理系统,国土安全部建立了管道维抢修应急响应程序,为具有不同事故原因、规模、地理位置或复杂性的事故提供了体系化处理方法,并基于社区规模、地理位置或自愿组织机构等进行人员和设备配置。以阿拉斯加州管道维抢修应急响应系统为例,详细介绍了应急响应队伍和人员的配置特点,应急反应资源的配备方式、影响因素和分布情况,可为国内油气管道维抢修应急响应工作的开展提供借鉴。石蕾 郝建斌 郭正虹 He Xihua Li Jinwu Feng Maoqi 2010油气储运2010,29,12:18
2Optimization design and experiment on ripple surface type pickup finger of precision maize seed metering device显示文摘A ripple surface type pickup finger was designed to improve the performance of pickup finger precision maize seed metering device and to provide a solution for precision maize planter.The main structure and working principle of seed metering device were detailed in this paper.The dimension size distributions of maize seeds in different types were studied,the gestures of seeds clamped by pickup finger were analyzed,and the clamping dynamical model of pickup finger was established by theoretical analysis.To optimize the structural parameters of ripple surface type pickup finger,the discrete element method(DEM)model of pickup finger precision maize seed metering device was established by the discrete element software EDEM.The numerical simulations of orthogonal seeding performance experiments were conducted to analyze the influences of these factors on the quality of seeding.The rotational speed,wavelength of ripple surface and amplitude of ripple surface were selected as the experimental factors.The average seeding qualified index and the average seeding coefficient of variation on four different types of maize seeds were chosen for evaluating the seeding performance.The results showed that,the average seeding qualified index was 93.35%and the average seeding coefficient of variation was 11.23%under conditions of the 25 r/min rotational speed,8 mm wavelength of ripple surface and 2 mm amplitude of ripple surface.Under the same condition,the bench test was done which showed that the results of test and simulation were consistent.The maximum error of qualified index was 1.95%and the qualified index of improved seed metering device exceeded the original one by 12.34%.The working performance can meet the requirements of precision maize seeding.Wang Jinwu Tang Han Wang Jinfeng Li Xin Huang Huinan 2017International Journal of Agricultural and Biological Engineering2017,10,1:14
3Recent advance in nonlinear aeroelastic analysis and control of the aircraft显示文摘A review on the recent advance in nonlinear aeroelasticity of the aircraft is presented in this paper. The nonlinear aeroelastic problems are divided into three types based on different research objects,namely the two dimensional airfoil,the wing,and the full aircraft. Different nonlinearities encountered in aeroelastic systems are discussed firstly,where the emphases is placed on new nonlinear model to describe tested nonlinear relationship. Research techniques,especially new theoretical methods and aeroelastic flutter control methods are investigated in detail. The route to chaos and the cause of chaotic motion of two-dimensional aeroelastic system are summarized. Various structural modeling methods for the high-aspect-ratio wing with geometric nonlinearity are discussed. Accordingly,aerodynamic modeling approaches have been developed for the aeroelastic modeling of nonlinear high-aspect-ratio wings. Nonlinear aeroelasticity about high-altitude longendurance(HALE) and fight aircrafts are studied separately. Finally,conclusions and the challenges of the development in nonlinear aeroelasticity are concluded. Nonlinear aeroelastic problems of morphing wing,energy harvesting,and flapping aircrafts are proposed as new directions in the future.Xiang Jinwu Yan Yongju Li Daochun 2014Chinese Journal of Aeronautics2014,27,1:14
4Three-dimensional bioprinting of multicell-laden scaffolds containing bone morphogenic protein-4 for promoting M2 macrophage polarization and accelerating bone defect repair in diabetes mellitus显示文摘Critical-sized bone defect repair in patients with diabetes mellitus remains a challenge in clinical treatment because of dysfunction of macrophage polarization and the inflammatory microenvironment in the bone defect region.Three-dimensional(3D)bioprinted scaffolds loaded with live cells and bioactive factors can improve cell viability and the inflammatory microenvironment and further accelerating bone repair.Here,we used modified bioinks comprising gelatin,gelatin methacryloyl(GelMA),and 4-arm poly(ethylene glycol)acrylate(PEG)to fabricate 3D bioprinted scaffolds containing BMSCs,RAW264.7 macrophages,and BMP-4-loaded mesoporous silica nanoparticles(MSNs).Addition of MSNs effectively improved the mechanical strength of GelMA/gelatin/PEG scaffolds.Moreover,MSNs sustainably released BMP-4 for long-term effectiveness.In 3D bioprinted scaffolds,BMP-4 promoted the polarization of RAW264.7 to M2 macrophages,which secrete anti-inflammatory factors and thereby reduce the levels of pro-inflammatory factors.BMP-4 released from MSNs and BMP-2 secreted from M2 macrophages collectively stimulated the osteogenic differentiation of BMSCs in the 3D bioprinted scaffolds.Furthermore,in calvarial critical-size defect models of diabetic rats,3D bioprinted scaffolds loaded with MSNs/BMP-4 induced M2 macrophage polarization and improved the inflammatory microenvironment.And 3D bioprinted scaffolds with MSNs/BMP-4,BMSCs,and RAW264.7 cells significantly accelerated bone repair.In conclusion,our results indicated that implanting 3D bioprinted scaffolds containing MSNs/BMP-4,BMSCs,and RAW264.7 cells in bone defects may be an effective method for improving diabetic bone repair,owing to the direct effects of BMP-4 on promoting osteogenesis of BMSCs and regulating M2 type macrophage polarization to improve the inflammatory microenvironment and secrete BMP-2.Xin Sun Zhenjiang Ma Xue Zhao Wenjie Jin Chenyu Zhang Jie Ma Lei Qiang Wenhao Wang Qian Deng Han Yang Jinzhong Zhao Qianqian Liang Xiaojun Zhou Tao Li Jinwu Wang 2021Bioactive Materials2021,6,3:12
5Virtual simulation analysis and verification of seed-filling mechanism for dipper hill-drop precision direct rice seeder显示文摘In order to improve the seeder’seed-filling ability of the dipper hill-drop precision direct rice seeder,and to meet the mechanization requirement of high speed operation,the self-designed seeder was taken as the objective to explore its seed-filling mechanism and the movement status of rice seed in seed box from the perspective of mechanics.The force models of seed-filling process by dipper were established,and the influential regularity of its rotation speed to compressive resistance of seed population was analyzed as well.The image processing Module-Clipping of discrete element simulation software EDEM was used in the virtual simulation analysis for the process of the seed filling into the dipper,and the velocity relation curve and the force changing curve between rotation speed and seeds were obtained.According to the virtual experiment,the composite filling force of seeds,i.e.the qualified rate on filled rice seed amounts was the largest when rotation speed was at 40 r/min.The performance test bed of seeder was used to verify the simulation results,in which the qualified rate on scooped rice seed amounts was taken as the index,and six rotation speeds of seed-filling dipper were also selected for analysis of seed-filling ability of the device.The results are as follows:with the increase of working speed,the qualified rate on filled rice seed amounts fluctuated with a trend of cosine curve,the largest value was 94.16%occurred when the rotation speed of seed-filling dipper was at 40 r/min.The variation trend of simulation value was approximately consistent with that of verification value.The study can provide a reference for the research and development of mechanical seeder.Wang Jinwu Zhou Wenqi Tian Liquan Li Shuwei Zhang Zhao 2017International Journal of Agricultural and Biological Engineering2017,10,6:7
6Aeroservoelastic modeling and analysis of a canard-configured air-breathing hypersonic vehicles显示文摘Air-breathing hypersonic vehicles (HSVs) are typically characterized by interactions of elasticity, propulsion and rigid-body flight dynamics, which may result in intractable aeroservoelastic problem. When canard is added, this problem would be even intensified by the introduction of low-frequency canard pivot mode. This paper concerns how the aeroservoelastic stability of a canard-configured HSV is affected by the pivot stiffnesses of all-moveable horizontal tail (HT) and canard. A wing/pivot system model is developed by considering the pivot torsional flexibility, fuselage vibration, and control input. The governing equations of the aeroservoelastic system are established by combining the equations of rigid-body motion, elastic fuselage model, wing/pivot system models and actuator dynamics. An unsteady aerodynamic model is developed by steady Shock-Expansion theory with an unsteady correction using local piston theory. A baseline controller is given to provide approximate inflight characteristics of rigid-body modes. The vehicle is trimmed for equilibrium state, around which the linearized equations are derived for stability analysis. A comparative study of damping ratios, closed-loop poles and responses are conducted with varying controller gains and pivot stiffnesses. Available bandwidth for control design is discussed and feasible region for pivot stiffnesses of HT and canard is given.Zeng Kaichun Xiang Jinwu Li Daochun 2013Chinese Journal of Aeronautics2013,26,4:7
7Coagulation factors VII, IX and X are effective antibacterial proteins against drug-resistant Gram-negative bacteria显示文摘Infections caused by drug-resistant“superbugs”pose an urgent public health threat due to the lack of effective drugs;however, certain mammalian proteins with intrinsic antibacterial activity might be underappreciated. Here, we reveal an antibacterial property against Gram-negative bacteria for factors VII, IX and X, three proteins with well-established roles in initiation of the coagulation cascade. These factors exert antibacterial function via their light chains (LCs). Unlike many antibacterial agents that target cell metabolism or the cytoplasmic membrane, the LCs act by hydrolyzing the major components of bacterial outer membrane, lipopolysaccharides, which are crucial for the survival of Gram-negative bacteria. The LC of factor VII exhibits in vitro efficacy towards all Gram-negative bacteria tested, including extensively drug-resistant (XDR) pathogens, at nanomolar concentrations. It is also highly effective in combating XDR Pseudomonas aeruginosa and Acinetobacter baumannii infections in vivo. Through decoding a unique mechanism whereby factors VII, IX and X behave as antimicrobial proteins, this study advances our understanding of the coagulation system in host defense, and suggests that these factors may participate in the pathogenesis of coagulation disorder-related diseases such as sepsis via their dual functions in blood coagulation and resistance to infection. Furthermore, this study may offer new strategies for combating Gram-negative “superbugs”.Jinwu Chen Xiaojie Li Ling Li Ting Zhang Qing Zhang Fangming Wu Diyue Wang Hongze Hu Changlin Tian Dongsheng Liao Liang Zhao Danxia Song Yongyun Zhao Chuanfang Wu Xu Song 2019Cell Research2019,29,9:6
8Aerodynamic Performance of the Locust Wing in Gliding Mode at Low Reynolds Number显示文摘Jinwu Xiang Jianxun Du Daochun Li Kai Liu 2016Journal of Bionic Engineering2016,13,2:6
9Identification of differentially expressed genes in rat silicosis model by suppression subtractive hybridization analysis显示文摘在肺的纤维变性的发展的批评分子的机制仍然保持未知,让有差的预后的病人诊断。孤立在肺的纤维变性明确地起来调整的基因,我们建立了一个老鼠矽肺模型在有水晶的硅石暂停的治疗以后的 360 d。胸的拍证明一些散布高密度的阴影出现在肺地里。典型显微镜的小谎 rosing silicotic 小瘤在肺,牙槽的上皮的房间和支气管的上皮的房间形成了,特别地在部分 fibrosing silicotic 小瘤附近;他们中的一些显示出建议了在矽肺和肺癌症之间的关联的不正常的增生。抑制减少性的杂交分析被执行在肺织物把基因表示与矽肺和正常的肺织物作比较。反向的抄写聚合酶链反应证明七个新奇 cDNA 序列的表情由在有矽肺的肺织物的减少性的杂交不同于的抑制识别了正常的肺织物。生物信息学分析证明 47 积极克隆代表了包含二通常认为的蛋白质的 35 基因,四预言了类似的蛋白质。分析也证明一些在矽肺屏蔽了基因,例如 prolyl 4-hydroxylases,肌动朊相关的 protein-2/3 建筑群和酸的哺乳动物的 chitinase,以前没被报导。这些基因可以为在肺的纤维变性的发展调查分子的机制提供新线索。Zhongyuan Jin Baoan Liu Deyun Feng Chen Chen Xiang Li Yongbin Hu Jinwu Peng Yu Liu Jing Du Chunyan Fu Jifang Wen 2008Acta Biochimica et Biophysica Sinica2008,40,8:6
10Challenges and developments of automotive fuel cell hybrid power system and control显示文摘Fuel cells are emerging as promising power sources and have attracted increasing attention from industries and academics worldwide. In particular, automotive manufacturers are replacing internal combustion engines in vehicles with fuel cell systems, which are advantaged by zero emissions, high efficiency,and various clean routes that generate pure hydrogen. However, current fuel cell systems are costly, and their corresponding infrastructures are not fully qualified to meet current market demand. This paper reviews the challenges and developments of automotive fuel cell hybrid power systems and their controls. It briefly summarizes the model, control, and optimization issue associated with the research and application of fuel cells in hybrid power systems. After presenting the basic knowledge and discussing the trending size and structure of fuel cells for automotive usage, the review describes models of automotive fuel cell systems,focusing on the electrochemical reaction dynamics and the key parameters influencing their efficiency and lifetime. The control problems associated with automotive fuel cell systems as well as the optimization issue associated with hybrid energy systems(comprising fuel cells, batteries, and ultra-capacitors) are elaborately analyzed. The review concludes with current problems and challenges faced by the energy control systems of fuel cell vehicles.Jinwu GAO Meng LI Yunfeng HU Hong CHEN Yan MA 2019Science China(Information Sciences)2019,62,5:6
11Measurement and analysis of restitution coefficient between maize seed and soil based on high-speed photography显示文摘The restitution coefficient is an important elementary physical parameter related to the research and development of agricultural machinery.The kinematic model of maize seed in the falling and impacting processes was developed to measure the restitution coefficient between maize seed and soil.A test bench for measuring the restitution coefficient was designed and built referred to the theory of mirror reflection.The velocities for impacting maize seed were measured and analyzed in a three-dimensional space via high-speed photography,and then restitution coefficients of in different impact conditions were obtained.On this basis,this study took flat dent seed and round seed as samples.Single factor tests were conducted to analyze the influences of these factors on the restitution coefficient.The impact angle,falling height,soil compaction,soil moisture,maize moisture content and different parts of seed were selected as test factors.The corresponding regression equations were obtained by analysis.The results showed that,as the impact angle was bigger than 25°,the restitution coefficient increased with the increase of impact angle.The restitution coefficient had a linear decreasing trend with the increase of falling height.As the soil compaction strength was 200-350 kPa,the restitution coefficient increased with the increase of soil compaction.As the soil compaction strength was larger than 350 kPa,the changing trend of the restitution coefficient was relatively stable.As the soil moisture content was 13.5%-18%,the restitution coefficient decreased with the increase of soil moisture.As the soil moisture content was 18%,the restitution coefficient was the minimum.As the maize moisture content was 11%-16%,the restitution coefficient decreased with the increase of maize moisture content.The rotational motion always occurred in falling process of flat dent seed and round seed.The probabilities of crown part and lateral part of maize seed impacting with soil were the highest,and the restitution coefficient between crown part and soil was higher than that of other parts in the same condition.Wang Jinwu Tang Han Wang Jinfeng Jiang Dongxuan Li Xin 2017International Journal of Agricultural and Biological Engineering2017,10,3:4
12Multi-objective robust airfoil optimization based on non-uniform rational B-spline (NURBS) representation显示文摘In order to improve airfoil performance under different flight conditions and to make the performance insensitive to off-design condition at the same time,a multi-objective optimization approach considering robust design has been developed and applied to airfoil design. Non-uniform rational B-spline (NURBS) representation is adopted in airfoil design process,control points and related weights around airfoil are used as design variables. Two airfoil representation cases show that the NURBS method can get airfoil geometry with max geometry error less than 0.0019. By using six-sigma robust approach in multi-objective airfoil design,each sub-objective function of the problem has robustness property. By adopting multi-objective genetic algorithm that is based on non-dominated sorting,a set of non-dominated airfoil solutions with robustness can be obtained in the design. The optimum robust airfoil can be traded off and selected in these non-dominated solutions by design tendency. By using the above methods,a multi-objective robust optimization was conducted for NASA SC0712 airfoil. After performing robust airfoil optimization,the mean value of drag coefficient at Ma0.7-0.8 and the mean value of lift coefficient at post stall regime (Ma0.3) have been improved by 12.2% and 25.4%. By comparing the aerodynamic force coefficients of optimization result,it shows that: different from single robust airfoil design which just improves the property of drag divergence at Ma0.7-0.8,multi-objective robust design can improve both the drag divergence property at Ma0.7-0.8 and stall property at low speed. The design cases show that the multi-objective robust design method makes the airfoil performance robust under different off-design conditions.LIANG Yu, CHENG XiaoQuan, LI ZhengNeng & XIANG JinWu School of Aeronautic Science and Engineering, Beihang University, Beijing 100191, China 2010Science China(Technological Sciences)2010,53,10:4
13Design and experimental study of a new flapping wing rotor micro aerial vehicle显示文摘A three-wing Flapping Wing Rotor Micro Aerial Vehicle(FWR-MAV)which can perform controlled flight is introduced and an experimental study on this vehicle is presented.A mechanically driven flapping rotary mechanism is designed to drive the three flapping wings and generate lift,and control mechanisms are designed to control the pose of the FWR-MAV.A flight control board for attitude control with robust onboard attitude estimation and a control algorithm is also developed to perform stable hovering flight and forward flight.A series of flight tests was conducted,with hovering flight and forward flight tests performed to optimize the control parameters and assess the performance of the FWR-MAV.The hovering flight test shows the ability of the FWR-MAV to counteract the moment generated by rotary motion and maintain the attitude of the FWR-MAV in space;the experiment of forward flight shows that the FWR-MAV can track the desired attitude.Xin DONG Daochun LI Jinwu XIANG Ziyu WANG 2020Chinese Journal of Aeronautics2020,33,12:3
14Injectable bioactive polymethyl methacrylate-hydrogel hybrid bone cement loaded with BMP-2 to improve osteogenesis for percutaneous vertebroplasty and kyphoplasty显示文摘Poly methyl methacrylate(PMMA)bone cement is used in augmenting and stabilizing fractured vertebral bodies through percutaneous vertebroplasty(PVP)and percutaneous kyphoplasty(PKP).However,applications of PMMA bone cement are limited by the high elasticity modulus of PMMA,its low biodegradability,and its limited ability to regenerate bone.To improve PMMA bio activity and biodegradability and to modify its elasticity modulus,we mixed PMMA bone cement with oxidized hyaluronic acid and carboxymethyl chitosan in situ cross-linking hydrogel loaded with bone morphogenetic protein-2(BMP-2)to achieve novel hybrid cement.These fabric ated PMMA-hydrogel hybrid cements exhibited lower setting temperatures,a lower elasticity modulus,and better biodegradability and biocompatibility than that of pure PMMA cement,while retaining acceptable setting times,mechanical strength,and inj ectability.In addition,we detected release of BMP-2 from the PMMA-hydrogel hybrid cements,significantly enhancing in vitro osteogenesis of bone marrow mesenchymal stem cells by up-regulating the gene expression of Runx2,Coll,and OPN.Use of PMMA-hydrogel hybrid cements loaded with BMP-2 on rabbit femoral condyle bone-defect models revealed their biodegradability and enhanced bone formation.Our study demonstrated the favorable mechanical properties,biocompatibility,and biodegradability of fabricated PMMA-hydrogel hybrid cements loaded with BMP-2,as well as their ability to improve osteogenesis,making them a promising material for use in PKP and PVP.Xin Sun Xin Zhang Xin Jiao Jie Ma Xingzhen Liu Han Yang Kangping Shen Yaokai Gan Jinwu Wang Haiyan Li Wenjie Jin 2022Bio-Design and Manufacturing2022,5,2:3
15A modified airfoil-based piezoaeroelastic energy harvester with double plunge degrees of freedom显示文摘In this letter,a piezoaeroelastic energy harvester based on an airfoil with double plunge degrees of freedom is proposed to additionally take advantage of the vibrational energy of the airfoil pitch motion.An analytical model of the proposed energy harvesting system is built and compared with an equivalent model using the well-explored pitch-plunge configuration.The dynamic response and average power output of the harvester are numerically studied as the flow velocity exceeds the cut-in speed(flutter speed).It is found that the harvester with double-plunge configuration generates 4%–10% more power with varying flow velocities while reducing 6% of the cut-in speed than its counterpart.Yining Wu Daochun Li Jinwu Xiang Andrea Da Ronch 2016Theoretical & Applied Mechanics Letters2016,6,5:2
16A novel imprecise stochastic process model for time-variant or dynamic uncertainty quantification显示文摘This paper proposes a novel model named as “imprecise stochastic process model” to handle the dynamic uncertainty with insufficient sample information in real-world problems. In the imprecise stochastic process model, the imprecise probabilistic model rather than a precise probability distribution function is employed to characterize the uncertainty at each time point for a time-variant parameter, which provides an effective tool for problems with limited experimental samples. The linear correlation between variables at different time points for imprecise stochastic processes is described by defining the auto-correlation coefficient function and the crosscorrelation coefficient function. For the convenience of analysis, this paper gives the definition of the P-box-based imprecise stochastic process and categorizes it into two classes: parameterized and non-parameterized P-box-based imprecise stochastic processes. Besides, a time-variant reliability analysis approach is developed based on the P-box-based imprecise stochastic process model,through which the interval of dynamic reliability for a structure under uncertain dynamic excitations or time-variant factors can be obtained. Finally, the effectiveness of the proposed method is verified by investigating three numerical examples.Jinwu LI Chao JIANG 2022Chinese Journal of Aeronautics2022,35,9:2
17Effect of low-frequency pulse percutaneous electric stimulation on peripheral nerve injuries at different sites显示文摘BACKGROUND: The postoperative recovery of nerve function in patients with peripheral nerve injury is always an important problem to solve after treatment. The electric stimulation induced electromagnetic field can nourish nerve, postpone muscular atrophy, and help the postoperative neuromuscular function. OBJECTIVE: To observe the effects of low-frequency pulse percutaneous electric stimulation on the functional recovery of postoperative patients with peripheral nerve injury, and quantitatively evaluate the results of electromyogram (EMG) examination before and after treatment. DESIGN: A retrospective case analysis. SETTING: The Sixth People’s Hospital affiliated to Shanghai Jiaotong University. PARTICIPANTS: Nineteen postoperative inpatients with peripheral nerve injury were selected from the Department of Orthopaedics, the Sixth People’s Hospital affiliated to Shanghai Jiaotong University from June 2005 to January 2006, including 13 males and 6 females aged 24-62 years with an average of 36 years old. There were 3 cases of brachial plexus nerve injury, 3 of median nerve injury, 7 of radial nerve injury, 3 of ulnar nerve injury and 3 of common peroneal nerve injury, and all the patients received probing nerve fiber restoration. Their main preoperative manifestations were dennervation, pain in limbs, motor and sensory disturbances. All the 19 patients were informed with the therapeutic program and items for evaluation. METHODS: ① Low-frequency pulse percutaneous electric stimulation apparatus: The patients were given electric stimulation with the TERESA cantata instrument (TERESA-0, Shanghai Teresa Health Technology, Co.,Ltd.). The patients were stimulated with symmetric square waves of 1-111 Hz, and the intensity was 1.2-5.0 mA, and it was gradually adjusted according to the recovered conditions of neural regeneration following the principle that the intensity was strong enough and the patients felt no obvious upset. They were treated for 4-24 weeks, 10-30 minutes for each time, 1-3 times a day, and 6 weeks as a course. ② EMG examination was applied to evaluate the recoveries of recruitment, motor conduction velocity (MCV) and sensory conduction velocity (SCV) before and after treatment. The patients were examined with the EMG apparatus (DISA2000C, Danmark) before and after the treatment of percutaneous electric stimulation. ③ Standards for evaluating the effects included cured (complete recovery of motor functions, muscle strength of grade 5, no abnormality in EMG examination), obviously effective [general recovery of motor function, muscle strength of grade 4, no or a few denervation potentials, motor conduction velocity (MCV) and sensory conduction velocity (SCV)], improved (partial recovery of motor function, muscle strength of grade 3, denervation potentials and reinneration potentials, slowed MCV and SCV, invalid (no obvious changes of motor function). MAIN OUTCOME MEASURES: ① Ameliorated degree of the nerve function of the postoperative patients with peripheral nerve injury treated with percutaneous electric stimulation; ② Changes of EMG examination before and after treatment. RESULTS: All the 19 postoperative patients with peripheral nerve injury were involved in the analysis of results. ① Comparison of nerve function before and after treatment in 19 patients with peripheral nerve injury of different sites: For the patients with radial nerve injury (n=7), the nerve functions all completely recovered after 8-week treatment, and the cured and obvious rate was 100% (7/7); For the patients with brachial plexus nerve injury (n=3), 1 case had no obvious improvement, and the cured and obvious rate was 67% (2/3); For the patients with common peroneal nerve injury (n=3), the extension of foot dorsum generally recovered in 1 case of nerve contusion after 4-week treatment, and the cured and obvious rate was 67% (2/3); For the patients with median nerve injury (n=3), muscle strength was obviously recovered, and the cured and obvious rate was 100% (3/3); For the patients with ulnar nerve injury (n=3), 1 case only had recovery of partial senses, and the cured and obvious rate was 67% (2/3). Totally 9 cases were cured, 7 were obviously effective, 1 was improved, and only 2 were invalid. After 4 courses, the cured rate of damaged nerve function after four courses was 47% (9/19), and effective rate was 89% (17/19). ② Comparison of EMG examination before and after treatment: Before and after percutaneous electric stimulation, he effective rates of recruitment, MCV and SCV were 89% (17/19), 58% (11/19), 47% (9/19) respectively, and there were extremely obvious differences (P < 0.01). CONCLUSION: ① Low-frequency pulse percutaneous electric stimulation can improve the nerve function of postoperative patients with peripheral nerve injury of different sites, especially that the injuries of radial nerve and median nerve recover more obviously. ②Percutaneous electric stimulation can ameliorate the indexes of EMG examination, especially the recruitment, in postoperative patients with peripheral nerve injury.Jinwu Wang Liye Chen Qi Li Weifeng Ni Min Zhang Shangchun Guo Bingfang Zeng 2006Neural Regeneration Research2006,1,3:1
18Aerodynamic characteristics of morphing wing withflexible leading-edge显示文摘The morphing wing can improve the flight performance during different phases.However,research has been subject to limitations in aerodynamic characteristics of the morphing wing with a flexible leading-edge.The computational fluid dynamic method and dynamic mesh were used to simulate the continuous morphing of the flexible leading-edge.After comparing the steady aerodynamic characteristics of morphing and conventional wings,this study examined the unsteady aerodynamic characteristics of morphing wings with upward and downward deflections of the leading-edge at different frequencies.The numerical results show that for the steady aerodynamic,the leading-edge deflection mainly affects the stall characteristic.The downward deflection of the leading-edge increases the stall angle of attack and nose-down pitching moment.The results are opposite for the upward deflection.For the unsteady aerodynamic,at a small angle of attack,the transient lift coefficient of the upward deflection,growing with the increase of deflection frequency,is larger than that of the static case.The transient lift coefficient of the downward deflection,decreasing with the increase of deflection frequency,is smaller than that of the static case.However,at a large angle of attack,an opposite effect of deflection frequency on the transient lift coefficient was demonstrated.The transient lift coefficient is larger than that of the static case when the leading edge is in the nose-up stage,and lower than that of the static one in the nose-down stage.Zi KAN Daochun LI Tong SHEN Jinwu XIANG Lu ZHANG 2020Chinese Journal of Aeronautics2020,33,10:1
19Design and experiment of spray and rotary tillage combined disinfection machine for soil显示文摘A spray and rotary tillage combined disinfection machine for soil was designed to solve the serious problems of plant diseases and insect pests,and it was divided into two operations which were soil disinfection and rotary tillage.The main structure and working principle of this machine were illustrated and analyzed.The reasonable structural parameters of the key parts of this machine were optimized,such as spraying disinfection system and rotary tillage land preparation system.To optimize the working performance and obtain better operation parameters,the orthogonal experiments were carried out to analyze the influences of three factors(forward speed of driving machine,rotational speed of rotary tillage,and working pressure)on the working performance.The mixing uniformity coefficient and the variation coefficient of spraying were selected for evaluating working performance.The range analysis and variance analysis were studied based on experimental data.The results showed that,the mixing uniformity coefficient of spraying was 93.95%and the variation coefficient was 6.01%with a working speed of 3 km/h,rotational speed of 2000 r/min and working pressure of 2.0 MPa.The machine can meet the agronomic requirements of disinfection and plowing,which was designed simply,compactly and strong applicability.The results can provide a guidance and technical support for preventing the plant diseases and insect pests,developing sustainable and ecological agriculture and improving the efficiency of compound cultivation.Jinwu Wang Wenpan Yang Xiaobo Sun Xiang Li Han Tang 2019International Journal of Agricultural and Biological Engineering2019,12,1:1
20Cu-clusters nodes of 2D metal-organic frameworks as a cost-effective noble-metal-free cocatalyst with high atom-utilization efficiency for efficient photocatalytic hydrogen evolution显示文摘Several 2D nanosheets of porphyrin MOFs with various transition-metal clusters as metal nodes were prepared via a simple solvothermal method to apply in the photocatalytic hydrogen evolution,in which the hydrogen production rate of the optimal NS-Cu was as high as 15.39 mmol g^(-1)h^(-1).A series of experimental technologies especially cyclic voltammetry(CV)and Mott-Schottky(M-S)had been adopted to investigate the charge-transfer property of photo-generated electron-hole pairs,it was found that the uniformly dispersed Cu-clusters nodes in the original 2D MOFs played a key role in the electron transfer process,that was,the photo-generated electron transferred from excited state eosin-Y to the Cu-clusters nodes for the efficient hydrogen evolution.The excellent photocatalytic performance could be attributed to the reversible oxidation-–reduction process of Cu^(Ⅱ)/Cu^(Ⅰ),which had excellent electron-receiving and electron-outputting capabilities.Our results provided a novel avenue to adapt the uniformly dispersed metal nodes in the original MOFs as cost-effective noble-metal-free cocatalysts with very high atomutilization efficiency to improve the photocatalytic hydrogen evolution performance in dye-sensitized system.Guangmei Jiang Xingyan Liu Huilong Jian Peng Lu Jinwu Bai Guizhi Zhang Wen Yun Siqi Li Youzhou He 2022Chinese Chemical Letters2022,33,6:1
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