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1KINEMATICS FEATURE ANALYSIS OF A 3-DOF COMPLIANT MECHANISM FOR MICRO MANIPULATION显示文摘Kinematics and its related issues of a 3-DOF in-parallel compliant mechanism are focused on.The micro manipulation application that requires high accuracy is developed.Design of the developed micromanipulator is based on the modified Delta mechanism.The main advantages of this manipulator are the use of only revolute flexure hinges and the capability to produce pure translation theoretically.The aim is to develop an efficient kinematic model used for positioning control.For this purpose, the Jacobian matrix relating the end effector position with the actuator displacements is obtained by both theoretical derivation and experiment.Aiming at the abnormality in the motion capabilities of the micromanipulator found in calibration experiment, the mobility of the compliant mechanism on a theoretical level is analyzed by using the matrix method and screw theory.Both the experimental and theoretical results have verified that the compliant mechanism does have rotational motion.YuJingjun HuYida BiShusheng ZongGuanghua ZhaoWei 2004Chinese Journal of Mechanical Engineering2004,17,1:22
2Current status of diagnosis and treatment of bladder cancer in China-Analyses of Chinese Bladder Cancer Consortium database显示文摘Objective:To investigate current status of diagnosis and treatment of bladder cancer in China.Methods:A database was generated by Chinese Bladder Cancer Consortium(CBCC).From January 2007 to December 2012,14,260 cases from 44 CBCC centers were included.Data of diagnosis,treatment and pathology were collected.Results:The average age was 63.5 year-old and most patients were male(84.3%).The most common histologic types were urothelial carcinoma(91.4%),adenocarcinoma(1.8%),and squamous carcinoma(1.9%).According to 1973 and 2004 WHO grading system,42.0%,41.0%,and 17.0% of patients were grade 1,2,and 3,and 16.0%,48.7%,and 35.3% of patients were papillary urothelial neoplasms of low malignant potential,low,and high grade,respectively.Non-muscle invasive bladder cancer(NMIBC)and muscle invasive bladder cancer(MIBC)were 25.2% and 74.1%,respectively(0.8% not clear).Carcinoma in situ was only 2.4%.Most patients were diagnosed by white-light cystoscopy with biopsy(74.3%).Fluorescence and narrow band imaging cystoscopy had additional detection rate of 1.0% and 4.0%,respectively.Diagnostic transurethral resection(TUR)provided detection rate of 16.9%.Most NMIBCs were treated with TUR(89.2%).After initial TUR,2.6%accepted second TUR,and 45.7%,69.9%,and 58.7% accepted immediate,induced,and maintenance chemotherapy instillation,respectively.Most MIBCs were treated with radical cystectomy(RC,59.7%).Laparoscopic RCs were 35.1%,while open RC 63.4%.Extended and standard pelvic lymph node dissection were 7% and 66%,respectively.Three most common urinary diversions were orthotopic neobladder(44%),ileal conduit(31%),and ureterocutaneostomy(23%).Only 2.3% of patients accepted neo-adjuvant chemotherapy and only 18%of T3 and T4 patients accepted adjuvant chemotherapy.Conclusion:Disease characteristics are similar to international reports,while differences of diagnosis and treatment exist.This study can provide evidences for revisions of the guideline on bladder cancer in China.Kaiwen Li Tianxin Lin Wei Xue Xin Mu Enci Xu Xu Yang Fubao Chen Guangyong Li Lulin Ma Guoliang Wang Chaozhao Liang Haoqiang Shi Ming Li Mao Tang Xueyi Xue Yisong Lv Yaoliang Deng Chengyang Li Zhiwen Chen Xiaozhou Zhou Fengshuo Jin Xudong Liu Jinxin Wei Lei Shi Xin Gou Weiyang He Liqun Zhou Lin Cai Baiye Jin Guanghou Fu Xiangbo Kong Hongyan Sun Ye Tian Lang Feng Tiejun Pan Yiyi Wu Dongwen Wang Hailong Hao Benkang Shi Yaofeng Zhu Qiang Wei Ping Han Changli Wu Dawei Tian Zhangqun Ye Zheng Liu Zhiping Wang Junqiang Tian Lin Qi Minfeng Chen Wei Li Jinchun Qi Gongxian Wang Longlong Fu Zhaolin Sun Guangheng Luo Zhoujun Shen Zhaowei Zhu Jinchun Xing Zhun Wu Dong Wei Xin Chen Yanqun Na Hongfeng Guo Chunxi Wang Zhihua Lu Chuize Kong Yang Liu Jin Yang Jianyun Hu Xin Gao Jielin Li Changjun Yin Pu Li Shan Chen Zhen Du Jiongming Li Yongji Yan Xu Zhang Shuang Huang Fangjian Zhou Zhiling Zhang Yinghao Sun Shuxiong Zeng Song Cen Jiaquan Zhou Hanzhong Li Jin Wen Jian Huang 2015Asian Journal of Urology2015,2,2:21
3Factors predicting sensory and motor recovery after the repair of upper limb peripheral nerve injuries显示文摘OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles describing outcomes after the repair of median, ulnar, radial, and digital nerve injuries in humans with a publication date between 1 January 1990 and 16 February 2011. STUDY SELECTION: The following types of article were selected:(1) clinical trials describing the repair of median, ulnar, radial, and digital nerve injuries published in English; and(2) studies that reported sufficient patient information, including age, mechanism of injury, nerve injured, injury location, defect length, repair time, repair method, and repair materials. SPSS 13.0 software was used to perform univariate and multivariate logistic regression analyses and to investigate the patient and intervention factors associated with outcomes. MAIN OUTCOME MEASURES: Sensory function was assessed using the Mackinnon-Dellon scale and motor function was assessed using the manual muscle test. Satisfactory motor recovery was defined as grade M4 or M5, and satisfactory sensory recovery was defined as grade S3+ or S4.RESULTS: Seventy-one articles were included in this study. Univariate and multivariate logistic regression analyses showed that repair time, repair materials, and nerve injured were independent predictors of outcome after the repair of nerve injuries(P < 0.05), and that the nerve injured was the main factor affecting the rate of good to excellent recovery. CONCLUSION: Predictors of outcome after the repair of peripheral nerve injuries include age, gender, repair time, repair materials, nerve injured, defect length, and duration of follow-up.Bo He Zhaowei Zhu Qingtang Zhu Xiang Zhou Canbin Zheng Pengliang Li Shuang Zhu Xiaolin Liu Jiakai Zhu 2014Neural Regeneration Research2014,9,6:12
4Ore Genesis of the Kalatongke Cu-Ni Sulfide Deposits, Western China: Constraints from Volatile Chemical and Carbon Isotopic Compositions显示文摘The Kalatongke Cu-Ni sulfide deposits located in the East Junggar terrane, northern Xinjiang, western China are the largest magmatic sulfide deposits in the Central Asian Orogenic Belt (CAOB). The chemical and carbon isotopic compositions of the volatiles trapped in olivine, pyroxene and sulfide mineral separates were analyzed by vacuum stepwise-heating mass spectrometry. The results show that the released volatiles are concentrated at three temperature intervals of 200-400°C, 400-900°C and 900-1200°C. The released volatiles from silicate mineral separates at 400-900°C and 900-1200°C have similar chemical and carbon isotopic compositions, which are mainly composed of H2O (av. ~92 mol%) with minor H2, CO2, H2S and SO2, and they are likely associated with the ore-forming magmatic volatiles. Light δ13CCO2 values (from -20.86‰ to -12.85‰) of pyroxene indicate crustal contamination occurred prior to or synchronous with pyroxene crystallization of mantlederived ore-forming magma. The elevated contents of H2 and H2O in the olivine and pyroxene suggest a deep mantle-originated ore-forming volatile mixed with aqueous volatiles from recycled subducted slab. High contents of CO2 in the ore-forming magma volatiles led to an increase in oxygen fugacity, and thereby reduced the solubility of sulfur in the magma, then triggered sulfur saturation followed by sulfide melt segregation; CO2 contents correlated with Cu contents in the whole rocks suggest that a supercritical state of CO2 in the ore-forming magma system under high temperature and pressure conditions might play a key role in the assemblage of huge Cu and Ni elements. The volatiles released from constituent minerals of intrusion 1# have more CO2 and SO2 oxidized gases, higher CO2/CH4 and SO2/H2S ratios and lighter δ13CCO2 than those of intrusions 2# and 3#. This combination suggests that the higher oxidation state of the volatiles in intrusion 1# than intrusions 2# and 3#, which could be one of key ore-forming factors for large amounts of ores and high contents of Cu and Ni in intrusion 1#. The volatiles released at 200-400°C are dominated by H2O with minor CO2, N2+CO and SO2, with δ13CCO2 values (-25.66‰ to -22.98‰) within the crustal ranges, and are considered to be related to secondary tectonic-hydrothermal activities.FU Piaoer TANG Qingyan ZHANG Mmgjie ZHANG Zhaowei LI Liwu LI Wenyuan 2012Acta Geologica Sinica(English Edition)2012,86,3:11
5Bioaccumulation and translocation of cadmium in cole (Brassica campestris L.) and celery (Apium graveolens) grown in the polluted oasis soil,Northwest of China显示文摘A pot experiment was conducted to study the bioaccumulation and translocation of cadmium (Cd) in cole (Brassica campestris L.) and celery (Apium graveolens) grown in the Cd-polluted oasis soil,Northwest of China.The results showed that Cd in the unpolluted oasis soil was mainly bound to carbonate fraction (F2) and Fe-Mn oxide fraction (F3).However,marked change of Cd fractions was observed with increasing soil Cd concentrations,in which the concentration of Cd in F1 (exchangeable fraction),F2 and F3 increased significantly (p<0.001 for F1,F2 and F3).The growth of cole and celery could be facilitated by low concentrations of Cd,but inhibited by high concentrations.The correlation analysis between the fraction distribution coefficient of Cd in the soil and Cd concentration accumulated in the two vegetables showed that Cd in F1 in the soil made the greatest contribution on the accumulation of Cd in the two vegetables.The high bio-concentration factor and the translocation factor of Cd in both cole and celery were observed,and Cd had higher accumulation in the edible parts of the two vegetables.Therefore,both cole and celery grown in Cd-polluted oasis soil have higher risk to human health.And the two vegetables are not suitable to be cultivated as vegetables consumed by human in the Cd-polluted oasis soil.Yiming Yang Zhongren Nan Zhuanjun Zhao Zhaowei Wang Shengli Wang Xia Wang Wangqiang Jin Cuicui Zhao 2011Journal of Environmental Sciences2011,23,8:8
6Bio-inspired Flow Sensing and Prediction for Fish-like Undulating Locomotion: A CFD-aided Approach显示文摘Han Zhou Tianjiang Hu Kin Huat Low Lincheng Shen Zhaowei Ma Guangming Wang Haijun Xu 2015Journal of Bionic Engineering2015,12,3:7
7Channel Measurement and Path Loss Modeling from 220 GHz to 330 GHz for 6G Wireless Communications显示文摘Terahertz(THz)communication has been envisioned as a key enabling technology for sixthgeneration(6G).In this paper,we present an extensive THz channel measurement campaign for 6G wireless communications from 220 GHz to 330 GHz.Furthermore,the path loss is analyzed and modeled by using two single-frequency path loss models and a multiplefrequencies path loss model.It is found that at most frequency points,the measured path loss is larger than that in the free space.But at around 310 GHz,the propagation attenuation is relatively weaker compared to that in the free space.Also,the frequency dependence of path loss is observed and the frequency exponent of the multiple-frequencies path loss model is 2.1.Moreover,the cellular performance of THz communication systems is investigated by using the obtained path loss model.Simulation results indicate that the current inter-site distance(ISD)for the indoor scenario is too small for THz communications.Furthermore,the tremendous capacity gain can be obtained by using THz bands compared to using microwave bands and millimeter wave bands.Generally,this work can give an insight into the design and optimization of THz communication systems for 6G.Pan Tang Jianhua Zhang Haoyu Tian Zhaowei Chang Jun Men Yuxiang Zhang Lei Tian Liang Xia Qixing Wang Jingsuo He 2021China Communications2021,18,5:7
8Optimization of construction scheme and supporting technology for HJS soft rock tunnel显示文摘For a soft rock tunnel under high stress in jointed and swell soft rock(HJS), two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC2 D, and the deformation effects of the two construction schemes were verified by field tests. Based on engineering geological investigation and mechanical analysis of large deformations, the complex deformation mechanisms of stress expansion and structural deformation of the soft rock tunnel were confirmed,and support countermeasures from the complex deformation mechanism converted to a single type were proposed, and the support parameters were optimized by field tests. These technologies were proved by engineering practice, which produced significant technical and economic benefits.Wang Shuren Li Chunliu Liu Zhaowei Fang Junbo 2014International Journal of Mining Science and Technology2014,24,6:7
9Visible-light-driven enhanced antibacterial and biofilm elimination activity of graphitic carbon nitride by embedded Ag nanoparticles显示文摘有 photocatalytic 活动的半导体 nanomaterials 为许多应用有潜力。支持 photocatalytic 活动的一个有效方法在一个半导体上正在扔高贵金属 nanoparticles (NP ) ,自从 NP 作为禁止 photoexcited 电子洞对的快再结合并且从而提高反应的氧种类(ROS ) 的产生的优秀电子领受人扮演的高贵金属。此处,一个高度有效的平台, graphitic 碳氮化物( g-C <潜水艇class=“ a-plus-plus ”> 3 N <潜水艇class=“ a-plus-plus ”>有嵌入的 Ag nanoparticles 的 4 ) nanosheets ( Ag/g-C <潜水艇class=“ a-plus-plus ”> 3 N <潜水艇class=“ a-plus-plus ”> 4 ),被综合由一灵巧的线路。在可见轻照耀下面, Ag/g-C 的 ROS 生产<潜水艇class=“ a-plus-plus ”> 3 N <潜水艇class=“ a-plus-plus ”> 4 nanohybrids 极大地与太古的 g-C 相比被改进<潜水艇class=“ a-plus-plus ”> 3 N <潜水艇class=“ a-plus-plus ”> 4 nanosheets ,并且而且, nanohybrids 显示出驱散细菌的 biofilms 的提高的抗菌剂功效和能力。我们第一次证明 Ag/g-C < 潜水艇 class= “ a-plus-plus ” > 3 N < 潜水艇 class= “ a-plus-plus ” > 4 nanohybrids 是在可见的光下面的有效杀菌代理人照耀,和罐头也为 biofilm 提供一个新方法消除。Ag/g-C 的提高的抗菌剂性质和破坏 biofilm 能力 < 潜水艇 class= “ a-plus-plus ” > 3 N < 潜水艇 class= “ a-plus-plus ” > 4 nanohybrids 可以为许多提供生物医学的应用。Wei Bing Zhaowei Chen Hanjun Sun Peng Shi Nao Gao Jinsong Ren Xiaogang Qu 2015Nano Research2015,8,5:7
10Two-dimensional optical spatial differentiation and high-contrast imaging显示文摘Optical analog signal processing technology has been widely studied and applied in a variety of science and engineering fields, with the advantages of overcoming the low-speed and high-power consumption associated with its digital counterparts. Much attention has been given to emerging metasurface technology in the field of optical imaging and processing systems. Here, we demonstrate, for the first time, broadband two-dimensional spatial differentiation and high-contrast edge imaging based on a dielectric metasurface across the whole visible spectrum. This edge detection method works for both intensity and phase objects simply by inserting the metasurface into a commercial optical microscope. This highly efficient metasurface performing a basic optical differentiation operation opens up new opportunities in applications of fast,compactible and power-efficient ultrathin devices for data processing and biological imaging.Junxiao Zhou Haoliang Qian Junxiang Zhao Min Tang Qianyi Wu Ming Lei Hailu Luo Shuangchun Wen Shaochen Chen Zhaowei Liu 2021National Science Review2021,8,6:6
11Satellite proximate interception vector guidance based on differential games显示文摘This paper studies the proximate satellite interception guidance strategies where both the interceptor and target can perform orbital maneuvers with magnitude limited thrusts. This problem is regarded as a pursuit-evasion game since satellites in both sides will try their best to capture or escape. In this game, the distance of these two players is small enough so that the highly nonlinear earth-centered gravitational dynamics can be reduced to the linear Clohessy-Wiltshire(CW) equations. The system is then simplified by introducing the zero effort miss variables. Saddle solution is formulated for the pursuit-evasion game and time-to-go is estimated similarly as that for the exoatmospheric interception. Then a vector guidance is derived to ensure that the interception can be achieved in the optimal time. The proposed guidance law is validated by numerical simulations.Dong YE Mingming SHI Zhaowei SUN 2018Chinese Journal of Aeronautics2018,31,6:5
12AFM quantitative analysis and determination of shear angle of {259}_f martensitic surface relief显示文摘An attentive observation and quantitative analysis of {259}f martensitic surface relief in an Fe-23Ni-0.55C alloy are made by means of an atomic force microscope (AFM), and different martensitic variants' shear angles are determined in this paper. The experiments show that {259}f martensitic surface relief exhibits regular shape in many cases, which is in agreement with the prediction of invariant plane strain (IPS). Generally, {259}f martensitic surface relief appears to be 'N'-shaped, but it is tent-shaped in the case of zigzag-shaped martensite. The compressed deformation of parent phase diminishes the surface relief in size but with little change of its relief angle. {259}f martensitic surface relief, large or small, has approximately the same relief angles, exhibiting a good 'self-similar fractal'. The determined values of different {259}f martensitic variants' shear angles are in fine agreement with the prediction of Wechsler-Liberman-Read (W-L-R) theory, with only a slight difference of less than 3.65°.LIN Xiaoping, GU Nanju, ZHANG Yong, MENG Zhaowei and MA Xiaoli(Department of Materials Science and Technology, Hebei University of Technology, Tianjin 300130, China) 2002Progress in Natural Science:Materials International2002,12,10:5
13Nanosecond-pulsed, dual-wavelength, passively Q-switched ytterbium-doped bulk laser based on few-layer MoS2 saturable absorber显示文摘A compact saturable absorber mirror(SAM) based on few-layer molybdenum disulfide(MoS2) nanoplatelets was fabricated and successfully used as an efficient saturable absorber(SA) for the passively Q-switched solid-state laser at 1 μm wavelength. Pulses as short as 182 ns were obtained from a ytterbium-doped(Yb:LGGG) bulk laser Q-switched by the MoS2 SAM, which we believe to be the shortest one ever achieved from the MoS2 SAs-based Q-switched bulk lasers. A maximum average output power of 0.6 W was obtained with a slope efficiency of 24%,corresponding to single pulse energy up to 1.8 μJ. In addition, the simultaneous dual-wavelength Q-switching at 1025.2 and 1028.1 nm has been successfully achieved. The results indicate the promising potential of few-layer MoS2 nanoplatelets as nonlinear optical switches for achieving efficient pulsed bulk lasers.Fei Lou Ruwei Zhao Jingliang He Zhitai Jia Xiancui Su Zhaowei Wang Jia Hou Baitao Zhang 2015Photonics Research2015,3,2:5
14Scalable and ultrafast epitaxial growth of single-crystal graphene wafers for electrically tunable liquid-crystal microlens arrays显示文摘The scalable growth of wafer-sized single-crystal graphene in an energy-efficient manner and compatible with wafer process is critical for the killer applications of graphene in high-performance electronics and optoelectronics. Here, ultrafast epitaxial growth of single-crystal graphene wafers is realized on singlecrystal Cu90Ni10(1 1 1) thin films fabricated by a tailored two-step magnetron sputtering and recrystallization process. The minor nickel(Ni) content greatly enhances the catalytic activity of Cu, rendering the growth of a 4 in. single-crystal monolayer graphene wafer in 10 min on Cu90Ni10(1 1 1), 50 folds faster than graphene growth on Cu(1 1 1). Through the carbon isotope labeling experiments, graphene growth on Cu90Ni10(1 1 1) is proved to be exclusively surface-reaction dominated, which is ascribed to the Cu surface enrichment in the Cu Ni alloy, as indicated by element in-depth profile. One of the best benefits of our protocol is the compatibility with wafer process and excellent scalability. A pilot-scale chemical vapor deposition(CVD) system is designed and built for the mass production of single-crystal graphene wafers, with productivity of 25 pieces in one process cycle. Furthermore, we demonstrate the application of single-crystal graphene in electrically controlled liquid-crystal microlens arrays(LCMLA), which exhibit highly tunable focal lengths near 2 mm under small driving voltages. By integration of the graphene based LCMLA and a CMOS sensor, a prototype camera is proposed that is available for simultaneous light-field and light intensity imaging. The single-crystal graphene wafers could hold great promising for highperformance electronics and optoelectronics that are compatible with wafer process.Bing Deng Zhaowei Xin Ruiwen Xue Shishu Zhang Xiaozhi Xu Jing Gao Jilin Tang Yue Qi Yani Wang Yan Zhao Luzhao Sun Huihui Wang Kaihui Liu Mark H. Rummeli Lu-Tao Weng Zhengtang Luo Lianming Tong Xinyu Zhang Changsheng Xie Zhongfan Liu Hailin Peng 2019Science Bulletin2019,64,10:4
15Sugar Starvation Enhances Leaf Senescence and Genes Involved in Sugar Signaling Pathways Regulate Early Leaf Senescence in Mutant Rice显示文摘To clarify the complex regulatory relationship between changes in sugar content and leaf senescence during the grain-filling stage of rice,genotype-dependent differences in sugar content and the temporal transcriptional patterns of genes involved in sugar signaling pathways were determined in mutant rice exhibiting early leaf senescence and its wild type Zhefu 142.The effects of exogenous glucose or sucrose on the senescence of detached leaves under dark conditions were also investigated.Chlorophyll,soluble sugar,sucrose and fructose contents decreased,whereas electrolytic leakage and malondialdehyde levels increased in mutant leaves at the grain-filling stage.These results suggested that sugar starvation is positively correlated with the early leaf senescence of mutant plants.Detached leaf segments incubated in exogenous sugar solutions under dark conditions exhibited delayed senescence.The high expression of Hxk1 in leaves of mutant plants at the initial grain-filling stage suggested that Hxk1 is involved in the hexose-sensing process at the early stage of leaf senescence.The low expression levels of Hxk2 and Frk1 in the senescing leaves of mutant rice during the grain-filling stage are indicative of weakened hexose phosphorylation.In addition,the high expression levels of Su Sy1,Su Sy2 and Su Sy4 in leaves of mutant plants at the initial grain-filling stage are accompanied by the high transcript levels of SUT1,which favor sucrose translocation and remobilization from the early senescing leaves of mutant rice.The relatively reduced transcript levels of ch FBP,cy FBP,SPS1,SPS2 and SPS6 indicated that during the grain-filling stage,sucrose biosynthesis is weakened in the senescing leaves of mutant rice.LI Zhaowei ZHAO Qian CHENG Fangmin 2020Rice science2020,27,3:4
16Optimal Spectrum Sensing in Energy Harvesting Cognitive Radio Systems显示文摘In this paper,we consider a cognitive radio system with energy harvesting,in which the secondary user operates in a saving-sensing-transmitting(SST) fashion.We investigate the tradeoff between energy harvesting,channel sensing and data transmission and focus on the optimal SST structure to maximize the SU's expected achievable throughput.We consider imperfect knowledge of energy harvesting rate,which cannot be exactly known and only its statistical information is available.By formulating the problem of expected achievable throughput optimization as a mixed-integer non-linear programming one,we derive the optimal saveratio and number of sensed channels with indepth analysis.Simulation results show that the optimal SST structure outperforms random one and performance gain can be enhanced by increasing the SU's energy harvesting rate.QU Zhaowei SONG Qizhu YIN Sixing 2014China Communications2014,11,5:4
17Cargo-encapsulated cells for drug delivery显示文摘Synthetic micro-/nanoparticle(MNP)carriers,either organic or inorganic ones,have advanced considerably in recent years for drug delivery with the aim of enhancing drug solubility/stability,reducing systemic toxicity and increasing dosing at pathological sites(Chen and Liang,2018;Xiang et al.,2018).Specially,the properties of MNPs,such as size,morphology,or surface groups,can be easily modulated to maximize their potency in delivering drugs to the targeted areas(Ran and Xue,2018).Nevertheless,till now,only a handful of MNPs have been approved by the US Food and Drug Administration for clinical application.Although numerous proof-of-concept studies of MNPs in animal models are in progress or are being clinically evaluated,synthetic MNPs are still struggling to reach the clinical expectations.Zhaowei Chen Di Wen Zhen Gu 2020Science China(Life Sciences)2020,63,4:4
18Joint Power Allocation and Mode Selection for D2D Communications with Imperfect CSI显示文摘Device-to-device(D2D) communications can be underlaid with a cellular infrastructure to increase resource utilization, improve user throughput and save battery energy. In such networks, power allocation and mode selection are crucial problems. To address the joint optimization of power and mode selection under imperfect CSI, we propose an optimal, energy-aware joint power allocation and mode selection(JPAMS) scheme. First, we derive the closed-form solution for the power minimization for both D2 D and cellular links while satisfying different quality of service(Qo S) constraints. Second, we address the mode selection problem in presence of imperfect CSI, based on the derived power allocation. Moreover, the theoretical analysis and simulation results are presented to evaluate the proposed scheme for the D2 D communications.MA Bei ZHANG Hailin ZHANG Zhaowei 2015China Communications2015,12,7:4
19Low-cost and high safe manganese-based aqueous battery for grid energy storage and conversion显示文摘As an effective energy storage technology, rechargeable batteries have long been considered as a promising solution for grid integration of intermittent renewables(such as solar and wind energy). However,their wide application is still limited by safety issue and high cost. Herein, a new battery chemistry is proposed to satisfy the requirements of grid energy storage. We report a simple Cu-Mn battery, which is composed of two separated current collectors in an H2SO4-CuSO4-MnSO4 electrolyte without using any membrane. The Cu-Mn battery shows an energy density of 40.8 Wh L-1, a super-long life of 10,000 cycles(without obvious capacity decay) and negligible self-discharge. And the capital cost of US$ 11.9 kWh-1 based on electrolyte is lower than any previous batteries. More importantly, the battery can still work smoothly during thermal abuse test and drill-through test, showing high safe nature. Furthermore, a combination system integrating the Cu-Mn battery and hydrogen evolution is also proposed, which is able to avoid the generation of explosive H2/O2 mixture, and presents an efficient approach for grid energy storage and conversion.Jianhang Huang Zhaowei Guo Xiaoli Dong Duan Bin Yonggang Wang Yongyao Xia 2019Science Bulletin2019,64,23:4
20Geology,Geochemistry and Minerogenesis of the Shijuligou Zinc-Copper Deposit in Gansu,China显示文摘The Shijuligou deposit was separated by an arcuate ductile shear zone cross the center of the deposit region, resulting in the difference between the southern and northern ore bodies. The lead (Pb) isotopic data of ores of the Shijuligou copper deposit have averages of 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb in 17.634, 15.444, and 37.312, respectively. It has been shown that ore-forming metals originated from intrusive and extrusive rocks in the upper part of ophiolites. The sulfur isotopic data of pyrite and chalcopyrite in the northern part change from +7.61‰ to +8.09‰ and +4.95‰ to +8.88‰ in the southern part. Isotopes of δ18O in the Shijuligou copper deposit are between +11.1‰ and +18.6‰, with the calculated δ18OH2O at +0.65‰. It is suggested that the mineralized fluid is a mixture of magma fluid, meteorological water, and seawater through circulating and leaching metals from the volcanic rocks. The zircon uranium-lead (U-Pb) dating of gabbro is 457.9±1.2 Ma, and the lower crossing age of the discordant and concordia curves of pyroxene spilite of zircon is 454±15 Ma. It is indicated that the Shijuligou deposit formed in a new ocean crust (ophiolite) of the back-arc basin in the late Ordovician. Mineralization should occur in the intermittence period after strong volcanic activity, and the age should be the late Ordovician. Moreover, the mineralization of ophiolite-hosted massive sulfide deposits in the ancient orogenic belt of the late Ordovician in the northern Qilian Mountains was controlled by the primary fault/fracture, with the forming of a metallogenic hydrothermal system by a mixture of volcanic magma fluid and seawater, which circularly leached the metallogenic metals from the volcanic rocks, resulting in their accumulation. The ore bodies were transformed with morphology and metallogenic elements. Jasperoid is an important sign for prospecting such deposits. There were many island arcs in the continent of China. This study provides evidence for understanding and exploration of ophiolite-hosted massive sulfide deposits in western China, especially in the area of northern Qilian Mountains.LI Wenyuan DENG Jun GAO Yongbao GUO Zhouping ZHANG Zhaowei SONG Zhongbao 2009Acta Geologica Sinica(English Edition)2009,83,6:3
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