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Grass Litter Decomposition Rate and Water-Holding Capacity in Dry-Hot Valley of jinshajiang River

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Wuhan University Journal of Natural Sciences 2009年第1期14卷 92-96页

作者： zhang Mingzhong ZHU Hongye jin Jie SHI Liangtao SHA Yucang Institute of Tropical Eco-Agricultural Sciences Yunnan Academy of Agriculture Sciences Yuanmou 651300 Yunnan China Science and Technological Division Yunnan Academy of Agricultural Sciences Kunming 650231 Yunnan China

The decomposition rate and the water-holding capacity of 6 kinds of grass litters were studied in the jinshajiang river dry-hot valley. The results showed that the dry weight remains reduced with time but did not have a direct correlation with time. The decomposition litters were affected by climate, character of litter, animalcule and soil animal. The climate factors of temperature and humidity were important especially. The water-holding capacity was in the sequence ofN. wightii （336%）, P. notatum Flugge （248%）, H. contortus （L.） Beauv （209%）, B. pertusa （L.） A. Camus（206%）, L endecaphylla Jacq （174%）, D. annulatum （Forsk.） Stapf （168%）. After 24 months decomposition the remaining dry weight of the litter was in the sequence as follows： 15.12% for N. wightii, 26.38% for I. endecaphylla Jacq, 27.23% for B. pertusa （L.） A. Camus, 30.78% for P. notatum Flugge, 39.72% for H. contortus （L.） Beauv and 39.76% for D. annulatum （Forsk.） Stapf. The decomposition rate and water-holding capacity ofN. wightii are at the highest level. It is important for the development, improvement and conservation of the grassland soil.

关键词： grass litter dry-hot river valley decomposition rate water- holding capacity

Analysis and Design of Hybrid Excitation Permanent Magnet Synchronous Generators

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Frontiers of Electrical and Electronic Engineering in China 2006年第1期1卷 63-66页

作者： jin Wan-bing zhang Dong AN Zhong-liang TAN Ren-yuan Delta Power Electronics Center Shanghai 201209China Shanghai University Shanghai 200072China Research Institute of Special Electric Machines Shenyang University of TechnologyShenyang 110023China

On the basis of a conventional permanent magnet(PM)synchronous generator’s construction,a novel kind of Hybrid Excitation Permanent Magnet Synchronous Generator(HEPMSG)is introduced by inserting exciting winding in the stator or ***,the construction of HEPMSG is improved with the addition of PM excitation on the ferromagnetic pole,and its working principle and design method are studied in ***,an appropriate exciting current control system is presented considering the characteristics of ***,a prototype is made,and test results confirm the analysis and design.

关键词： hybrid excitation complex magnet circuit PWM adjustive rate of voltage

Insight into vertical piezoelectric characteristics regulated thermal transport in van der Waals two-dimensional materials

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Rare Metals 2024年第2期43卷 770-779页

作者： Dong-Hai Wei E Zhou jin-Yuan Xu Hui-Min Wang Chen Shen Hong-Bin zhang Zhen-Zhen Qin Guang-Zhao Qin State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China Hunan Key Laboratory for Micro-Nano Energy Materials and Device and School of Physics and Optoelectronics Xiangtan UniversityXiangtan411105China Institute of Materials Science Technical University of DarmstadtAlarich-Weiss-Str.264287DarmstadtGermany School of Physics and Microelectronics Zhengzhou UniversityZhengzhou450001China

The urgent demand of extreme(ultra-high/low)thermal conductivity materials is triggered by the high-power device,where exploring the theories and mechanisms of regulating thermal transport properties plays a key ***,we elaborately investigate the effect of vertical(out-of-plane)piezoelectric characteristics on thermal transport,which is historically *** different stacking-order(AA and AB)bilayer boron nitride(Bi-BN)in two-dimensional(2D)materials are selected as study *** performing state-of-the-art first-principles calculations,it is found that the polarization charge along the out-of-plane orientation ascends significantly with the increasing piezoelectric response in AB stacked Bi-BN(Bi-BN-AB)followed by the enhanced interlayer B–N atomic ***,the amplitude of phonon anharmonicity in Bi-BN-AB increases larger than that in the AA stacked Bi-BN(Bi-BN-AA),resulting in the dramatic weakening of the thermal conductivity by 20.34%under 18%*** research reveals the significant role of the vertical(out-of-plane)piezoelectric characteristic in regulating thermal transport and provides new insight into accurately exploring the thermal transport performance of 2D van der Waals materials.

关键词： Thermal conductivity Piezoelectric effect 2D materials Bilayer BN Strain engineering

Preprocessing of Tandem Mass Spectrometric Data Based on Decision Tree Classification

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Genomics, Proteomics & Bioinformatics 2005年第4期3卷 231-237页

作者： jing-Fen zhang Si-Min He jin-jin Cai Xing-Jun Cao Rui-Xiang Sun Yan Fu Rong Zeng Wen Gao Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100080 China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China.

In this study, we present a preprocessing method for quadrupole time-of-flight （Q-TOF） tandem mass spectra to increase the accuracy of database searching for peptide （protein） identification. Based on the natural isotopic information inherent in tandem mass spectra, we construct a decision tree after feature selection to classify the noise and ion peaks in tandem spectra. Furthermore, we recognize overlapping peaks to find the monoisotopic masses of ions for the following identification process. The experimental results show that this preprocessing method increases the search speed and the reliability of peptide identification.

关键词： peptide identification Q-TOF tandem mass spectra feature selection decision tree

The anatomical,electrophysiological and histological observations of muscle contraction units in rabbits:a new perspective on nerve injury and regeneration

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Neural Regeneration Research 2022年第1期17卷 228-232页

作者： Ting-Min Xu Bo Chen Zong-Xue jin Xiao-Feng Yin Pei-Xun zhang Bao-Guo Jiang Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Center Peking University People’s HospitalBeijingChina National Trauma Medical Center BeijingChina Department of Rehabilitation Peking University People’s HospitalBeijingChina

In the conventional view a muscle is composed of intermediate structures before its further division into microscopic muscle *** experiments in mice have confirmed this intermediate structure is composed of the lamella cluster formed by motor endplates,the innervating nerve branches and the corresponding muscle fibers,which can be viewed as an independent structural and functional *** this study,we verified the presence of these muscle construction units in *** results showed that the muscular branch of the femoral nerve sent out 4–6 nerve branches into the quadriceps and the tibial nerve sent out 4–7 nerve branches into the *** each nerve branch of the femoral nerve was stimulated from the most lateral to the medial,the contraction of the lateral muscle,intermediate muscle and medial muscle of the quadriceps could be induced by electrically stimulating at least one nerve *** stimulating each nerve branch of the tibial nerve from the lateral to the medial,the muscle contraction of the lateral muscle 1,lateral muscle 2,lateral muscle 3 and medial muscle of the gastrocnemius could be induced by electrically stimulating at least one nerve *** stimulation of each nerve branch resulted in different electromyographical waves recorded in different muscle ***-eosin staining showed most of the nerve branches around the neuromuscular junctions consisted of one individual neural tract,a few consisted of two or more neural *** muscles of the lower limb in the rabbit can be subdivided into different muscle subgroups,each innervated by different nerve branches,thereby allowing much more complex muscle activities than traditionally ***,the nerve branches and the innervated muscle subgroups can be viewed as an independent structural and functional *** study was approved by the Animal Ethics Committee of Peking University People’s Hospital(approval No.2019 PHE027)on October 20,2019.

关键词： anatomy electrophysiology femoral nerve hematoxylin-eosin staining gastrocnemius motor endplate muscle contraction unit peripheral nerve quadriceps rabbit skeletal muscle tibial nerve

Flexible triboelectric nanogenerator toward ultrahigh-frequency vibration sensing

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Nano Research 2022年第8期15卷 7484-7491页

作者： Zhiwei Lin Chenchen Sun Gaoqiang zhang Endong Fan Zhihao Zhou Ziying Shen Jun Yang Mingyang Liu Yushu Xia Shaobo Si jin Yang Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) Department of Optoelectronic EngineeringChongqing UniversityChongqing 400044China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

Flexible high-frequency vibration sensors are highly desirable in various real-world applications such as structural health monitoring,environmental monitoring,and the internet of ***,developing a facile and effective method to fabricate vibration sensors simultaneously featuring high vibration frequency response-ability and flexibility remains a grand ***,we report a flexible ultrahigh-frequency triboelectric vibration sensor(UTVS)prepared by a layer-particle-layer *** to the flexibility of the materials(i.e.,polyethylene terephthalate membrane)and the ultrahigh-frequency vibration response-ability of internal microparticles,the flexible UTVS exhibits an enhanced working frequency range of 3–170 kHz,which is much broader than previously reported triboelectric vibration ***,the UTVS can work not only in a flat state but also in a bent state due to its flexibility and the unique layer-particle-layer structural *** UTVS shows nanometer-level vibration response-ability,omnidirectional response,stability in the temperature range of 10–70°C,good frequency resolution of 0.01 kHz,and excellent performance in burst vibration detection(e.g.,pencil lead break events and impact events from falling steel balls).With a collection of compelling features,the device is successfully demonstrated in vibration monitoring of curved structures(e.g.,real-time water pipeline leak monitoring).Such a flexible ultrahigh-frequency triboelectric vibration sensor holds great potential in a wide range of practical applications,such as communication,health care,and infrastructure monitoring.

关键词： vibration sensing structural health monitoring flexible electronics self-powered sensor

InAs/InAsSb type-Ⅱ superlattice with near room-temperature long-wave emission through interface engineering

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Rare Metals 2022年第3期41卷 982-991页

作者： Bo-Wen zhang Dan Fang Xuan Fang Hong-Bin Zhao Deng-Kui Wang jin-Hua Li Xiao-Hua Wang Dong-Bo Wang State Key Laboratory of High Power Semiconductor Lasers School of ScienceChangchun University of Science and TechnologyChangchun 130022China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China Department of Opto-electronic Information Science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

Ga-free InAs/InAsSb type-Ⅱ superlattices(T2SL) have extensive application prospective in infrared photodetectors. Achieving higher operation temperature is critical to its commercial applications. Here, a fractional monolayer alloy method was used to grow InAsSb alloy with better controlled alloy composition. The as-grown T2SL gave eleven satellite peaks and a first satellite peak with a narrow full-width-half-maximum (FWHM) of 20.5arcsec (1 arcsec=0.01592°). Strain mapping results indicated limited Sb diffusion through the As-Sb exchange process at the interface. Moreover, unlike interface states caused by the As-Sb exchange effect, this relatively clear interface was distinctive with localized states with higher activation energies of the non-radiative recombination process ((18±1) meV and (84±12) meV at different temperature ranges), which means that this interface state introduced by fractional monolayer alloy growth method can effectively suppress Auger recombination process in T2SL. Through this interface engineering of InAs/InAsSb Type-Ⅱ superlattice, it achieved detective photoluminescence (PL) signal with the center wavelength of 9μm at 250K.

关键词： InAs/InAsSb Superlattice Interface states High operation temperature emission

Hot Deformation Behavior of Low Carbon Steel during Compression at Elevated Temperature

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Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 601-605页

作者：刘和平 LIU Bin LI Dazhao SUN Hu'er SUN Feng'er jin Xuejun zhang Yongtao School of Materials Science and Engineering North University of China School of Materials Science and Engineering Shanghai Jiao Tong University School of Machinery Shanghai DianJi University

Hot compression tests of low carbon steel were carried out on Gleeble-3500 system in the temperature range from 750 to 900 ℃ and in the strain rate range from 0.001 to 1.0 s^-1, and the associated microstructural evolution was studied by observations with a metallographic microscope. The results show that the stress-strain curves exhibit a peak stress at critical strain, after which the flow stresses *** monotonically until reaching high strains, showing a dynamic flow softening. The peak stress level decreases with increasing deformation temperature and decreasing strain rate, which can be represented by the Zener-Hollomon parameter Z in the hyperbolic sine equation. The flow stress increases with increasing strain rate and decreasing deforming temperature. The flow stress can be described by constitutive equation in hyperbolic sine function and can also be described by a Zener-Hollomon parameter Z. With increasing deformation temperature and deereasing strain rate, the grain size as well as the volume fraction of the reerystaUized grains increase. The safe region for hot working of the alloy has been determined according to the processing map and microstructure at the true strain of 0.5, which is the deformation temperature of 840-940 ℃ and the strain rate of 0.001-1.0 s^-1.

关键词： hot deformation dynamic recrystallization constitutive equation processing map

Synergistic mechanisms of AMF and biochar driving rhizosphere fungal community in shallot in barren soil

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Horticultural Plant Journal 2024年第5期10卷 1252-1256页

作者： Zishan Li Yingyue Li Qing zhang Zihua zhang Jiaqing Jiang Tao Huang Chunge Mei Fulang Wu Beijiu Cheng Xiaoyu Li jin Chen National Engineering Laboratory of Crop Stress Resistance Breeding Schools of Life SciencesAnhui Agricultural UniversityHefeiAnhui 230036China

The addition of biochar(BC)or Arbuscular mycorrhizal fungi(AMF)alone has been reported to promote plant growth,while their synergistic effects on Allium schoenoprasum root morphology and rhizosphere fungal community in barren soil is still *** this study,we investigated the effects of BC and AMF(Funneliformis mosseae)on plant growth and root morphology in barren soil and revealed the structure of soil fungal communities Therefore,a greenhouse pot trial consisting of five treatments was *** results showed that the combination of biochar and AMF significantly improved plant biomass,nutrient uptake,mycorrhizal colonization rates and soil properties and significantly impacted rhizosphere fungal community composition and *** significantly increased the fungal community stability and enhanced their positive correlation with *** findings indicated that the combination of AMF and biochar play synergic role for plant growth and rhizosphere fungal community in barren soil.

关键词： soil rhizosphere barren