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125篇 您的检索式:作者名="Pengfei Cheng"
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1Early-Mid Ordovician brachiopod diversification in South China显示文摘Affected by paleogeographic position, paleoclimatic condition and depositional environments, the increase of the Early-Mid Ordovician brachiopod diversity of South China commenced at the beginning of the Ordovician (early Tremadoc), accelerated from the Tetra- graptus approximatus Biozone (base of Arenig), and reached its first acme in the Didymograptus eobifidus Biozone (mid early Arenig) when the number of brachiopod genera was over 7 times as great as that at the start of the Ordovician. This was the first radiation in the history of brachiopod macroevolution in South China, which occurred nearly 5 graptolitic biozones earlier than the global trend of the great Ordovician biodiversification (in the lower part of the Undulograptus austrodentatus Biozone). It is also characterized by (1) the origination or first occurrences of some major groups, such as the punctate dalmanelloids and the pseudopunctate stro- phomenoids including Plectambonitoidea (cardinal process simple or absent) and Stro- phomenoidea (cardinal process bilobed) in South China; (2) niche expansion, particularly in the first occupation of deeper water benthic regimes by the Euorthisina-Nocturnellia Association developed at Houping, Chengkou, northern Chongqing; and (3) the differentiation of brachiopod faunas under different environmental conditions. The gradual and increasing separation from Gondwana may have been one of the factors responsible for the radiation in South China.ZHAN Renbin, RONG Jiayu, CHENG Jinhui & CHEN Pengfei Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing 210008, China 2005Science China Earth Sciences2005,48,5:14
2The Chinese Hα Solar Explorer(CHASE) mission: An overview显示文摘The Chinese Hα Solar Explorer(CHASE), dubbed “Xihe”—Goddess of the Sun, was launched on October 14, 2021 as the first solar space mission of China National Space Administration(CNSA). The CHASE mission is designed to test a newly developed satellite platform and to acquire the spectroscopic observations in the Hα waveband. The Hα Imaging Spectrograph(HIS)is the scientific payload of the CHASE satellite. It consists of two observational modes: raster scanning mode and continuum imaging mode. The raster scanning mode obtains full-Sun or region-of-interest spectral images from 6559.7 to 6565.9 ? and from 6567.8 to 6570.6 ? with 0.024 ? pixel spectral resolution and 1 min temporal resolution. The continuum imaging mode obtains photospheric images in continuum around 6689 ? with the full width at half maximum of 13.4 ?. The CHASE mission will advance our understanding of the dynamics of solar activity in the photosphere and chromosphere. In this paper, we present an overview of the CHASE mission including the scientific objectives, HIS instrument overview, data calibration flow, and first results of on-orbit observations.Chuan Li Cheng Fang Zhen Li MingDe Ding PengFei Chen Ye Qiu Wei You Yuan Yuan MinJie An HongJiang Tao XianSheng Li Zhe Chen Qiang Liu Gui Mei Liang Yang Wei Zhang WeiQiang Cheng JianXin Chen ChangYa Chen Qiang Gu QingLong Huang MingXing Liu ChengShan Han HongWei Xin ChangZheng Chen YiWei Ni WenBo Wang ShiHao Rao HaiTang Li Xi Lu Wei Wang Jun Lin YiXian Jiang LingJie Meng Jian Zhao 2022Science China(Physics,Mechanics & Astronomy)2022,65,8:7
3New innovations in pavement materials and engineering:A review on pavement engineering research 2021显示文摘Sustainable and resilient pavement infrastructure is critical for current economic and environmental challenges.In the past 10 years,the pavement infrastructure strongly supports the rapid development of the global social economy.New theories,new methods,new technologies and new materials related to pavement engineering are emerging.Deterioration of pavement infrastructure is a typical multi-physics problem.Because of actual coupled behaviors of traffic and environmental conditions,predictions of pavement service life become more and more complicated and require a deep knowledge of pavement material analysis.In order to summarize the current and determine the future research of pavement engineering,Journal of Traffic and Transportation Engineering(English Edition)has launched a review paper on the topic of'New innovations in pavement materials and engineering:A review on pavement engineering research 2021'.Based on the joint-effort of 43 scholars from 24 well-known universities in highway engineering,this review paper systematically analyzes the research status and future development direction of 5 major fields of pavement engineering in the world.The content includes asphalt binder performance and modeling,mixture performance and modeling of pavement materials,multi-scale mechanics,green and sustainable pavement,and intelligent pavement.Overall,this review paper is able to provide references and insights for researchers and engineers in the field of pavement engineering.JTTE Editorial Office Jiaqi Chen Hancheng Dan Yongjie Ding Yangming Gao Meng Guo Shuaicheng Guo Bingye Han Bin Hong Yue Hou Chichun Hu Jing Hu Ju Huyan Jiwang Jiang Wei Jiang Cheng Li Pengfei Liu Yu Liu Zhuangzhuang Liu Guoyang Lu Jian Ouyang Xin Qu Dongya Ren Chao Wang Chaohui Wang Dawei Wang Di Wang Hainian Wang Haopeng Wang Yue Xiao Chao Xing Huining Xu Yu Yan Xu Yang Lingyun You Zhanping You Bin Yu Huayang Yu Huanan Yu Henglong Zhang Jizhe Zhang Changhong Zhou Changjun Zhou Xingyi Zhu 2021Journal of Traffic and Transportation Engineering(English Edition)2021,8,6:7
4Laparoscopic-assisted radical gastrectomy for distal gastric cancer显示文摘A 48-year-old female patient was diagnosed with a superficial depressed type early gastric cancer (type IIc) of 1.0 cm at the gastric angle as indicated by gastroscopy. Laparoscopic-assisted greater omentumpreserving D2 radical gastrectomy was performed in combination with Billroth I reconstruction under general anesthesia for the distal gastric cancer on April 5, 2013. The postoperative recovery was satisfying without complications. The patient was discharged seven days after surgery.Yian Du Xiangdong Cheng Zhiyuan Xu Litao Yang Ling Huang Bing Wang Pengfei Yu Ruizeng Dong 2013Chinese Journal of Cancer Research2013,25,4:6
5Possible mechanism underlying analgesic effect of Tuina in rats may involve piezo mechanosensitive channels within dorsal root ganglia axon显示文摘OBJECTIVE: To demonstrate the analgesic effect of Tuina mainly from mechanically sensitive ion channels in peripheral myelinated nerve fibers.METHODS: A total of 40 healthy and pathogen-free adult male Sprague-Dawley rats were used in the study [weight:(220.0 ± 1.4) g, Shanghai Slac Laboratory Animal Co., Ltd., Shanghai, China; license No. Shanghai ICP 05033115]. The rats were housed in cages with free access to water and food in a temperature-controlled room [(22 ± 1) ℃] and12-h/12-h light-dark cycle. Thirty-two rats were randomly divided into five groups: naive, sham, chronic compression of dorsal root ganglion(CCD), Tuina(7 d) and Tuina(21 d). CCD rat model was established via unilateral DRG compression by'L'liked steel bar. Chinese Tuina treatment was accepted once per day. Behavior monitoring of paw withdrawal threshold(PWT) and paw withdrawal latency(PWL) were tested. The expression of Piezo1 and Piezo2 in myelinated nerve fiber were analyzed by immunohistochemistry and Western-blotting.RESULTS: There was a high expression of Piezo2 and a low expression of Piezo1 in the naive and CCD groups. In contrast, the expression of Piezo2 was down regulated and Piezo1 was increased after a period of Tuina. There was significant difference(P ≤ 0.05) between the groups.CONCLUSION: Our findings suggest that Tuina therapy can increase the expression of Piezo2 and decrease the expression of Piezo1 in the test rats.The different changes in the expressions of Piezo1 and Piezo2 may play an important role in alleviating CCD-induced allodynia and hyperalgesia.Song Pengfei Lin Zhigang Zhu Qingguang Jiang Shichao Zhang Hao Cheng Yanbin Sun Wuquan Wu Zhiwei Zhou Xin Lv Zhizhen Fang Min 2018Journal of Traditional Chinese Medicine2018,38,6:6
6Amorphous Zr(OH)4 coated LiNi0.915Co0.075Al0.01O2 cathode material with enhanced electrochemical performance for lithium ion batteries显示文摘LiNi_(0.915)Co_(0.075)Al_(0.01)O_2(NCA) with Zr(OH)_4 coating is demonstrated as high performance cathode material for lithium ion batteries(LIBs). The coated materials are synthesized via a simple dry coating method of NCA with Zr(OH)_4 powders, and then characterized with scanning electron microscopy(SEM), transmission electron microscopy(TEM) and X-ray photoelectron spectroscopy(XPS). Experimental results show that amorphous Zr(OH)_4 powders have been successfully coated on the surface of spherical NCA particles, exhibiting improved electrochemical performance. 0.50 wt% Zr(OH)_4 coated NCA delivers a capacity of 197.6 mAh/g at the first cycle and 154.3 mAh/g after 100 cycles with a capacity retention of 78.1% at 1 C rate. In comparison, the pure NCA shows a capacity of 194.6 mAh/g at the first cycle and 142.5 mAh/g after 100 cycles with a capacity retention of 73.2% at 1 C rate. Electrochemical impedance spectroscopy(EIS) results show that the coated material exhibits a lower resistance, indicating that the coating layer can efficiently suppress transition metals dissolution and decrease the side reactions at the surface between the electrode and electrolyte. Therefore, surface coating with amorphous Zr(OH)_4 is a simple and useful method to enhance the electrochemical performance of NCA-based materials for the cathode of LIBs.Zhen Zhang Pengfei Zhou Huanju Meng Chengcheng Chen Fangyi Cheng Zhanliang Tao Jun Chen 2017Journal of Energy Chemistry2017,26,3:5
7Dust removal efficiency of high pressure atomization in underground coal mine显示文摘To master theoretical calculation for dust removal efficiency of high pressure atomization in an underground coal mine, the corresponding atomization characteristics and dust removal efficiency were both comprehensively studied in theory by virtue of related theories of hydromechanics and aerosol.According to actual measurements of flow coefficients and atomization angles of X-type swirl nozzle,computational formula was derived for atomized particle sizes of such a nozzle in conjunction with relevant empirical equation. Moreover, a mathematical model for applying high pressure atomization to dust removal in underground coal mine was also established to deduce theoretical computation formula of fractional efficiency. Then, Matlab was adopted to portray the relation curve between fractional efficiency and influence factors. In addition, a theoretical formula was also set up for removal efficiency of respirable dust and total coal dust based on dust size and frequency distribution equations. In the end,impacts of dust characteristic parameters on various dust removal efficiencies were analyzed.Pengfei Wang Xuanhao Tan Weimin Cheng Gang Guo Ronghua Liu 2018International Journal of Mining Science and Technology2018,28,4:5
8Realization of an Optimal Dynamic Geodetic Reference Frame in China:Methodology and Applications显示文摘China Geodetic Coordinate System 2000(CGCS2000)has been used for several years as a formal published reference frame.The coordinates of all global navigation satellite system(GNSS)stations in China need to be corrected to align with the CGCS2000 frame.Different strategies can be adopted for the realization of an optimal reference frame.However,different strategies lead to different results,with differences as great as several decimeters when GNSS station coordinates are transformed into CGCS2000-defined coordinates.The two common methods for the coordinate correction of a GNSS station are quasi-stable adjustment under CGCS2000 and plate movement correction,and the differences between their results can be greater than 10 cm.In this study,a statistic method called'supervised clustering'is applied to the selection of GNSS reference stations;a new scheme named'partition spacing'for the grouping of all processed GNSS stations is proposed;and the plate movement correction method is used to correct the coordinates of all GNSS stations from the GNSS epoch to the CGCS2000 epoch.The results from the new partitioning method were found to be significantly better than those from the conventional station-blocking approach.When coordinates from the stations without grouping were used as the standard,the accuracy of all the three-dimensional coordinate components from the new partitioning method was better than 2 mm.The root mean squares(RMSs)of the velocities in the x,y,and z directions resulting from the supervised clustering method were 0.19,0.45,and 0.32 mm∙a1,respectively,which were much smaller than the values of 0.92,0.72,and 0.97 mm∙a1 that resulted from the conventional approach.In addition,singular spectrum analysis(SSA)was used to model and predict the position nonlinear movements.The modeling accuracies of SSA were better than 3,2,and 5 mm in the east(E),north(N),and up(U)directions,respectively;and its prediction accuracies were better than 5 mm and 1 cm for the horizontal and vertical domains,respectively.Pengfei Cheng Yingyan Cheng Xiaoming Wang Suqin Wu Yantian Xu 2020Engineering2020,6,8:5
9The trend of the APRGP velocity field and plates movement derived from GPS data显示文摘High-precision data processing theories and methods for the wide area GPS network–––Asia Pacific Regional Geodesy Project (APRGP), are systematically discussed in this article. With the software bernese5.0 update, the annual results of APRGP coordinate, velocity field and the trend of plate movement are reestimated, and the corresponding accuracy of adjustment with different constraints, also the velocity field of APRGP, are presented and analyzed. Conclusions could be drawn that Eurasian plate (EURA) rotates clockwise, the Australian plate (AUST) and the Indian plate (INDI) move from southwest to northeast, while the Pacific plate (PCFC) is drifting to northwest, which shows agreement with those of IGS results.CHENG PengFei , WANG Hua, CHENG YingYan, WEN HanJiang & CAI YanHui Chinese Academy of Surveying and Mapping, Beijing 100039, China 2010Science China(Physics,Mechanics & Astronomy)2010,53,4:5
10D2 plus radical resection combined with perioperative chemotherapy for advanced gastric cancer with pyloric obstruction显示文摘A patient with advanced gastric cancer complicated with pyloric obstruction was treated using D2 + radical resection combined with perioperative chemotherapy, and had satisfying outcomes. The perioperative chemotherapy regimen was Taxol and S1 (tegafur, gimeracil, and oteracil). Three cycles of neoadjuvant chemotherapy were delivered before surgery, and three cycles of adjuvant therapy after surgery. PR was achieved after chemotherapy. D2 + dissection of stations 8p, 12b, 12p, 13 and 14v lymph nodes was performed on September 10, 2012.Yian Du Xiangdong Cheng Zhiyuan Xu Litao Yang Ling Huang Bing Wang Pengfei Yu Ruizeng Dong 2013Chinese Journal of Cancer Research2013,25,4:5
11Gas Sensors Based on Chemi?Resistive Hybrid Functional Nanomaterials显示文摘Chemi-resistive sensors based on hybrid functional materials are promising candidates for gas sensing with high responsivity,good selectivity,fast response/recovery,great stability/repeatability,room-working temperature,low cost,and easy-to-fabricate,for versatile applications.This progress report reviews the advantages and advances of these sensing structures compared with the single constituent,according to five main sensing forms:manipulating/constructing heterojunctions,catalytic reaction,charge transfer,charge carrier transport,molecular binding/sieving,and their combinations.Promises and challenges of the advances of each form are presented and discussed.Critical thinking and ideas regarding the orientation of the development of hybrid material-based gas sensor in the future are discussed.Yingying Jian Wenwen Hu Zhenhuan Zhao Pengfei Cheng Hossam Haick Mingshui Yao Weiwei Wu 2020Nano-Micro Letters2020,12,6:5
12Networking retinomorphic sensor with memristive crossbar for brain-inspired visual perception显示文摘Compared to human vision,conventional machine vision composed of an image sensor and processor suffers from high latency and large power consumption due to physically separated image sensing and processing.A neuromorphic vision system with brain-inspired visual perception provides a promising solution to the problem.Here we propose and demonstrate a prototype neuromorphic vision system by networking a retinomorphic sensor with a memristive crossbar.We fabricate the retinomorphic sensor by using WSe_(2)/h-BN/Al_(2)O_(3)van der Waals heterostructures with gate-tunable photoresponses,to closely mimic the human retinal capabilities in simultaneously sensing and processing images.We then network the sensor with a large-scale Pt/Ta/Hf O_(2)/Ta one-transistor-one-resistor(1 T1 R)memristive crossbar,which plays a similar role to the visual cortex in the human brain.The realized neuromorphic vision system allows for fast letter recognition and object tracking,indicating the capabilities of image sensing,processing and recognition in the full analog regime.Our work suggests that such a neuromorphic vision system may open up unprecedented opportunities in future visual perception applications.Shuang Wang Chen-Yu Wang Pengfei Wang Cong Wang Zhu-An Li Chen Pan Yitong Dai Anyuan Gao Chuan Liu Jian Liu Huafeng Yang Xiaowei Liu Bin Cheng Kunji Chen Zhenlin Wang Kenji Watanabe Takashi Taniguchi Shi-Jun Liang Feng Miao 2021National Science Review2021,8,2:5
13Co3O4 nanocage derived from metal-organic frameworks: An excellent cathode catalyst for rechargeable Li-O2 battery显示文摘Rechargeable non-aqueous Li-O2 battery is regarded as one of the most promising energy-storage technologies on account of its high energy density.It is believed that the rational design of three-dimensional (3D) architecture for catalyst is a key factor for the remarkable performance.Metal-organic frameworks (MOFs) derived materials possess excellent architecture,which is beneficial for Li-O2 batteries.In this work,ZIF-67 is used as precursor template and calcinated under different temperature to produce Co3O4 crystals.When the anneal treatment is under 350℃,the derived Co3O4 nanocage holds the most complete skeleton,which provides better charge transfer ability as well as O2 and Li^+ diffusion.Meanwhile,the Co3O4 nanocage owns more oxygen vacancies,offering more active sites.With the synergistic effect of nanocage structure and active sites,the Co3O4 nanocage stably delivers a large specific capacity of 15,500 mAh·g^-1 as well as a long cycle-life of 132 cycles at limited discharge capacity of 1,000 mAh·g^-1 under discharge/charge current density of 0.5 A·g^-1.Zhuoliang Jiang Hui Sun Wenke Shi Tianhang Zhou Jianyong Hu Jingyang Cheng Pengfei Hu Shigang Sun 2019Nano Research2019,12,7:5
14Update China geodetic coordinate frame considering plate motion显示文摘China Geodetic Coordinate System 2000(CGCS2000),as the formal national coordinate reference frame,has been used for 20 years.The coordinates of all Global Navigation Satellite System(GNSS)stations in China need referring to this system.To this end,the first step is to align the coordinates of all stations,usually included in a regional GNSS network,with a given International Terrestrial Reference Frame(ITRF),then these coordinates are corrected to the CGCS2000 in consideration of plate movement.For a better alignment result,regional control stations are needed and their coordinates were estimated from the combination of constraint-free normal equation systems provided by several International GNSS Service(IGS)analysis centers.The effect in using these refined coordinates,which deter-mine a regional coordinate datum,on the alignment result should be evaluated by the coordinate corrections of the regional control stations to the regional coordinate datum,i.e.smaller corrections mean better alignments of the two associated frames.The test results show that the refined coordinates are more accurate than the ones calculated from the station’s velocity,and are well aligned with the ITRF2005.Moreover,for obtaining the coordinates of GNSS stations in an updated CGCS2000 frame,a gridded linear velocity field based on the estimated velocities at 1025 CGCS2000 stations was generated for China's Mainland using the optimal interpolation method,the inverse distance weighting,which is selected from five interpolation methods.The overall precisions of the constructed velocity field at all stations in the East(E)and,North(N)directions are 0.78 mm/a and 0.95 mm/a,respectively.For evaluating the accuracy of the updated CGCS2000 frame,monthly solutions for the coordinates of some CGCS2000 CORS stations in the ITRF2014 during the period from 2000.0 to 2018 were obtained and the Root Mean Square(RMS)of the differences between the coordinates corrected to the CGCS2000 and the known coordinates at these stations are about 2-3 cm.Pengfei Cheng Yingyan Cheng Xiaoming Wang Yantian Xu 2021Satellite Navigation2021,2,1:4
152D hierarchical yolk-shell heterostructures as advanced host-interlayer integrated electrode for enhanced Li-S batteries显示文摘Lithium sulfur(Li-S)batteries hold great promising for high-energy-density batteries,but appear rapid capacity fading due to the lack of overall and elaborated design of both sulfur host and interlayer.Herein,we developed a novel two-dimensional(2D)hierarchical yolk-shell heterostructure,constructed by a graphene yolk,2D void and outer shell of vertically aligned carbon-mediated MoS2 nanosheets(G@void@MoS2/C),as advanced host-interlayer integrated electrode for Li-S batteries.Notably,the 2D void,with a typical thickness of^80 nm,provided suitable space for loading and confining nano sulfur,and vertically aligned ultrathin MoS2 nanosheets guaranteed enriched catalytically active sites to effectively promote the transition of soluble polysulfides.The conductive graphene yolk and carbon mediated shell sufficiently accelerated electron transport.Therefore,the integrated electrode of G@void@MoS2/C not only exceptionally confined the sulfur/polysulfides in 2D yolk-shell heterostructures,but also achieved catalytic transition of the residual polysulfides dissolved in electrolyte to solid Li2S2/Li2S,both of which synergistically achieved an extremely low capacity fading rate of 0.05%per cycle over 1000 times at 2C,outperforming most reported Mo based cathodes and interlayers for Li-S batteries.2D hierarchical yolkshell heterostructures developed here may shed new insight on elaborated design of integrated electrodes for Li-S batteries.Yanfeng Dong Pengfei Lu Haodong Shi Jieqiong Qin Jian Chen Wencai Ren Hui-Ming Cheng Zhong-Shuai Wu 2019Journal of Energy Chemistry2019,28,9:4
16Preparation and Tribological Properties of Lanthanum-doped Muscovite Composite Particles as Lubricant Additives in Lithium Grease显示文摘Lanthanum-doped muscovite(MC) composite particles(hereinafter abbreviated as La-MC) were prepared by the mechanical solid-state-chemistry-reaction method, followed by surface modification with oleic acid. The microstructure of materials was characterized by SEM, XRD, EDS and FTIR. Furthermore, the friction-reduction and anti-wear properties of MC and La-MC as lubricant additives in lithium grease were evaluated using a four-ball friction and wear tester. The results showed that La(OH)_3 nanoparticles were coated on the surface of muscovite. Both MC and La-MC can effectively improve the friction-reduction and anti-wear properties of lithium grease and La-MC presents better tribological properties than MC. The excellent tribological properties of La-MC can be attributed to the formation of the adsorbed La-MC film and the chemical reaction film mainly composed of Fe_2O_3 and SiO_2 on the worn surface, as well as the catalysis of lanthanum element during the friction process.Du Pengfei Chen Guoxu Song Shiyuan Zhao Litao Wu Jiang Cheng Peng Yang Xiao 2016China Petroleum Processing & Petrochemical Technology2016,18,2:4
17Enhanced mechanical property and tunable dielectric property of SiC_(f)/SiC-SiBCN composites by CVI combined with PIP显示文摘The SiBCN matrix via chemical vapor infiltration(CVI)or/and polymer infiltration pyrolysis(PIP)technologies was orderly introduced to SiC_(f)/SiC composites to optimize the mechanical property and electromagnetic(EM)shielding effectiveness simultaneously.The BN interface with the thickness of 350 nm was designed to obtain a little stronger interface bonding.The flexural strength of SiC_(f)/SiC-SiBCN composites reached 545.45±29.59 MPa thanks to the crack deflection between the CVI SiC and CVI SiBCN,as well as CVI SiBCN and PIP SiBCN matrix because of the modulus difference between them.The fracture toughness(KiC)with the value of 16.02±0.94 MPa·m^(1/2) was obtained owing to the extension of crack propagation path.The adverse effect of stronger interface bonding was eliminated by the design of matrix microstructure for SiC_(f)/SiC-SiBCN composites.The thermal conductivity in the thickness direction was 7.64 W·(m·K)^(-1) at 1200℃and the electric resistivity decreased to 1.53×10^(3) Ω·m.The tunable dielectric property was obtained with the coordination of wave-absorption CVI SiBCN matrix and impedance matching PIP SiBCN matrix,and the total shielding effectiveness(SE_(T))attained 30.01 dB.It indicates that the SiC_(f)/SiC-SiBCN composites have great potential to be applied as structural and functional materials.Chaokun SONG Yongsheng LIU Fang YE Laifei CHENG Pengfei ZHANG Nan CHAI 2021Journal of Advanced Ceramics2021,10,4:4
18Site-Dependent Osseointegration of Biodegradable High-Purity Magnesium for Orthopedic Implants in Femoral Shaft and Femoral Condyle of New Zealand Rabbits显示文摘Magnesium(Mg) has been widely accepted as osteoconductive biomaterial, but osseointegration of Mg device at different implantation sites is still unclear. In the present study, high-purity magnesium(HP Mg)pins were implanted into femoral shaft and condyle of New Zealand rabbits concurrently. 2, 8, 12 and 16 weeks after surgery, rabbit femurs were harvested for micro-computed tomography(micro-CT) scanning and subsequent histological examinations. HP Mg pins were retrieved for scanning electron microscope and energy dispersive spectrum(SEM/EDS) analyses. HP Mg pins at both implantation sites performed stable corrosion with mineral deposition and bone incorporation on surface. However, difference in distribution of contact osteogenesis centers and biological properties of peri-implant bone tissues was detected between femoral shaft and femoral condyle. In femoral condyle, contact osteogenesis centers originated from both periosteum and cancellous bones and the whole HP Mg pin was encapsuled in trabecular bone at 16 weeks.Meanwhile, bone volume to total bone volume(BV/TV) and bone mineral density(BMD) of peri-implant bone tissues were above those of normal bone tissues. In femoral shaft, contact osteogenesis centers were only from periosteum and direct bone contact was confined in cortical bone, while BV/TV and BMD kept lower than normal. Furthermore, new formation of peri-implant bone tissues was more active in femoral condyle than in femoral shaft at 16 weeks. Therefore, although HP Mg performed good biocompatibility and corrosion behavior in vivo, its bioadaption of osseointegration at different implantations sites should be taken into consideration. Bone metaphysic was suitable for Mg devices where peri-implant bone tissues regenerated rapidly and the biological properties were close to normal bone tissues.Pengfei Cheng Changli Zhao Pei Han Jiahua Ni Shaoxiang Zhang Xiaonong Zhang Yimin Chai 2016Journal of Materials Science & Technology2016,32,9:4
19Designandconstructionof athree-dimensionalelectrodewith biomass-derived carbon current collector andwater-soluble binder for high-sulfur-loading lithium-sulfur batteries显示文摘Lithium-sulfur batteries attract lots of attention due to their high specific capacity,low cost,and environmental friendliness.However,the low sulfur utilization and short cycle life extremely hinder their application.Herein,we design and fabricate a three-dimensional electrode by a simple filtration method to achieve a high-sulfur loading.Biomass porous carbon is employed as a current collector,which not only enhances the electronic transport but also effectively limits the volume expansion of the active material.Meanwhile,an optimized carboxymethyl cellulose binder is chosen.The chemical bonding restricts the shuttle effect,leading to improved electrochemical performance.Under the ultrahigh sulfur load of 28mg/cm2,the high capacity of 18mAh/cm2 is still maintained,and stable cycling performance is obtained.This study demonstrates a viable strategy to develop promising lithium-sulfur batteries with a three-dimensional electrode,which promotes sulfur loading and electrochemical performance.Pengfei Wang Zhe Gong Ke Ye Vipin Kumar Kai Zhu Linna Sha Jun Yan Jinling Yin Kui Cheng Guiling Wang Dianxue Cao 2020Carbon Energy2020,2,4:3
20Calibration procedures for the CHASE/HIS science data显示文摘The Hα line is an important optical line in solar observations containing the information from the photosphere to the chromosphere. To study the mechanisms of solar eruptions and the plasma dynamics in the lower atmosphere, the Chinese Hα Solar Explorer(CHASE) was launched into a Sun-synchronous orbit on October 14, 2021. The scientific payload of the CHASE satellite is the Hα Imaging Spectrograph(HIS). The CHASE/HIS acquires, for the first time, seeing-free Hα spectroscopic observations with high spectral and temporal resolutions. It consists of two observational modes. The raster scanning mode provides full-Sun or region-of-interest spectra at Hα(6559.7-6565.9 ?) and Fe I(6567.8-6570.6 ?) wavebands. The continuum imaging mode obtains full-Sun photospheric images at around 6689 ?. In this paper, we present detailed calibration procedures for the CHASE/HIS science data, including the dark-field and flat-field correction, slit image curvature correction, wavelength and intensity calibration, and coordinate transformation. The higher-level data products can be directly used for scientific research.Ye Qiu ShiHao Rao Chuan Li Cheng Fang MingDe Ding Zhen Li YiWei Ni WenBo Wang Jie Hong Qi Hao Yu Dai PengFei Chen XiaoSheng Wan Zhi Xu Wei You Yuan Yuan HongJiang Tao XianSheng Li YuKun He Qiang Liu 2022Science China(Physics,Mechanics & Astronomy)2022,65,8:3
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