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1Revealing of the ultrafast third-order nonlinear optical response and enabled photonic application in two-dimensional tin sulfide显示文摘Black phosphorus(BP), a typical mono-elemental and two-dimensional(2D) material, has gathered significant attention owing to its distinct optoelectronic properties and promising applications, despite its main obstacle of long-term stability. Consequently, BP-analog materials with long-term chemical stability show additional potential. In this contribution, tin sulfide(SnS), a novel two-elemental and 2D structural BP-analog monochalcogenide, has been demonstrated to show enhanced stability under ambient conditions. The broadband nonlinear optical properties and carrier dynamics have been systematically investigated via Z-scan and transient absorption approaches. The excellent nonlinear absorption coefficient of 50.5 × 10^-3 cm∕GW, 1 order of magnitude larger than that of BP, endows the promising application of SnS in ultrafast laser generation. Two different decay times of τ1~873 fs and τ2~96.9 ps allow the alteration between pure Q switching and continuous-wave(CW) mode locking in an identical laser resonator. Both mode-locked and Q-switched operations have been experimentally demonstrated using an SnS saturable absorber at the telecommunication window. Femtosecond laser pulses with tunable wavelength and high stability are easily obtained, suggesting the promising potential of SnS as an efficient optical modulator for ultrafast photonics. This primary investigation may be considered an important step towards stable and high-performance BP-analog material-based photonic devices.Zhongjian Xie Feng Zhang Zhiming Liang Taojian Fan Zhongjun Li Xiantao Jiang Hong Chen Jianqing Li Han Zhang 2019Photonics Research2019,7,5:13
2Complete genome sequence of the rifamycin SV-producing Amycolatopsis mediterranei U32 revealed its genetic characteristics in phylogeny and metabolism显示文摘Amycolatopsis mediterranei 被用于 rifamycin 的工业规模生产,它在 antimycobacterial 治疗起一个重要作用。作为类 Amycolatopsis 的首先定序的染色体, 236 715 底配对的包括 10 的紧张 U32 的染色体,最大的原核生物的染色体之一到目前为止曾经被定序。不同于在 streptomycetes 发现的线性拓扑学,这个染色体是圆形的,特别地类似于 Saccharopolyspora erythraea 和奴卡氏菌属 farcinica,在发展史和分类代表他们的靠近的关系。尽管在 A 预言了 9 228 编码蛋白质的基因。mediterranei 染色体 S 与那些分享了 orthologs 的最大的数字。erythraea,它被 Streptomyces coelicolor 而非 N 出人意料地跟随。farcinica,显示不同新陈代谢的特征经由改编演变到多样的生态的壁龛。除类似于那的一个核心区域以外在 streptomycetes 普通,有典型核心特征的一个新奇“伪核心”在非核心区域以内被定义,在 21 从 26 基因为第二等的代谢物生产聚类的总数被定位的地方。位于核心的 rifamycin 生合成基因簇为 rifamycin SV 的变换编码细胞色素 P450 酶必需品到 B,由比作 rifamycin 生产 B 紧张 S699 的高度相应的簇揭示了并且进一步由基因互补证实了。A 的 genomic 信息。mediterranei 表明在看起来复杂的规章的机制的控制下面不仅为各种各样的碳来源和无机的氮混合物的广泛的利用而且为新陈代谢的中介的有效 funneling 安排进第二等的抗菌素合成进程的一个新陈代谢的网络。Wei Zhao Yi Zhong Hua Yuan Jin Wang Huajun Zheng Ying Wang Xufeng Cen Feng Xu Jie Bai Xiaobiao Han Gang Lu Yongqiang Zhu Zhihui Shao Han Yan Chen Li Nanqiu Peng Zilong Zhang Yunyi Zhang Wei Lin Yun Fan Zhongjun Qin Yongfei Hu Baoli Zhu Shengyue Wang Xiaoming Ding Guo-Ping Zbao 2010Cell Research2010,20,10:10
3Three-dimensional-printed individualized porous implants:A new“implant-bone”interface fusion concept for large bone defect treatment显示文摘Bone defect repairs are based on bone graft fusion or replacement.Current large bone defect treatments are inadequate and lack of reliable technology.Therefore,we aimed to investigate a simple technique using three-dimensional(3D)-printed individualized porous implants without any bone grafts,osteoinductive agents,or surface biofunctionalization to treat large bone defects,and systematically study its long-term therapeutic effects and osseointegration characteristics.Twenty-six patients with large bone defects caused by tumor,infection,or trauma received treatment with individualized porous implants;among them,three typical cases underwent a detailed study.Additionally,a large segmental femur defect sheep model was used to study the osseointegration characteristics.Immediate and long-term biomechanical stability was achieved,and the animal study revealed that the bone grew into the pores with gradual remodeling,resulting in a long-term mechanically stable implant-bone complex.Advantages of 3D-printed microporous implants for the repair of bone defects included 1)that the stabilization devices were immediately designed and constructed to achieve early postoperative mobility,and 2)that osseointegration between the host bone and implants was achieved without bone grafting.Our osseointegration method,in which the“implant-bone”interface fusion concept was used instead of“bone-bone”fusion,subverts the traditional idea of osseointegration.Teng Zhang Qingguang Wei Hua Zhou Zehao Jing Xiaoguang Liu Yufeng Zheng Hong Cai Feng Wei Liang Jiang Miao Yu Yan Cheng Daoyang Fan Wenhao Zhou Xinhong Lin Huijie Leng Jian Li Xinyu Li Caimei Wang Yun Tian Zhongjun Liu 2021Bioactive Materials2021,6,11:9
4Partitioning properties of rare earth ores in China显示文摘The properties of rare earth partitioning in Chinese industrial rare earth ores were analyzed. Rare earth ores canbe divided into the single-mineral type ore with bastnaesite, the multi-mineral type ore with bastnaesite and monazite, andthe weathering crust type. Both the Bayan Obo rare earth ore and the Zhushan rare earth ore are a kind of mixed ore, con-sisting of bastnaesite and monazite. Their rare earth partitionings are strongly enriched in light rare earths, where CeO2 is50% and the light rare earth partitioning is totally over 95%. The Mianning rare earth ore as well as the Weishan rare earthis a kind of rare earth ore only having bastnaesite. Their rare earth partitionings are also strongly enriched in light rare earths,in which CeO2 is 47% and the light rare earth partitioning is totally over 94%. For the weathering crust type rare earth ore,there are the Longnan rare earth ore, the Xunwu rare earth ore, and the middle yttrium and rich europium ore. In the Long-nan rare earth ore, which is strongly enriched in heavy rare earths, Y2O3 is 64.83%, and the heavy and light rare earthpartitionings are 89.40% and 10.53%, respectively. In the Xunwu rare earth ore, which is strongly enriched in light rareearths, CeO2 is 47.16%, and the light rare earth partitioning is totally 93.25%. Y and Eu are enriched in the middle yttriumand rich europium ore. Its middle rare earth partitioning is totally over 10%, and Eu2O3 and Y2O3 are over 0.5% and 20%,respectively, which are mainly industrial resources of the middle and the heavy rare earths.CHI Ru 'an LI Zhongjun PENG Cui ZHU Guocai XU Shengming 2005Rare Metals2005,24,3:8
5Graphene/phosphorene nano-heterojunction:facile synthesis, nonlinear optics, and ultrafast photonics applications with enhanced performance显示文摘Owing to its thickness-modulated direct energy band gap, relatively strong light–matter interaction, and unique nonlinear optical response at a long wavelength, few-layer black phosphorus, or phosphorene, becomes very attractive in ultrafast photonics applications. Herein, we synthesized a graphene/phosphorene nano-heterojunction using a liquid phase-stripping method. Tiny lattice distortions in graphene and phosphorene suggest the formation of a nano-heterojunction between graphene and phosphorene nanosheets. In addition, we systematically investigate their nonlinear optical responses at different wavelength regimes. Our experiments indicate that the combined advantages of ultrafast relaxation, broadband response in graphene, and the strong light–matter interaction in phosphorene can be combined together by nano-heterojunction. We have further fabricated two-dimensional(2D) nano-heterojunction based optical saturable absorbers and integrated them into an erbium-doped fiber laser to demonstrate the generation of a stable ultrashort pulse down to 148 fs. Our results indicate that a graphene/phosphorene nano-heterojunction can operate as a promising saturable absorber for ultrafast laser systems with ultrahigh pulse energy and ultranarrow pulse duration. We believe this work opens up a new approach to designing 2D heterointerfaces for applications in ultrafast photonics and other research.The fabrication of a 2D nano-heterojunction assembled from stacking different 2D materials, via this facile and scalable growth approach, paves the way for the formation and tuning of new 2D materials with desirable photonic properties and applications.SHUNXIANG LIU ZHONGJUN LI YANQI GE HUIDE WANG RUI YUE XIANTAO JIANG JIANQING LI QIAO WEN HAN ZHANG 2017Photonics Research2017,5,6:6
6Siliceous Cementation of Chlorite-Coated Grains in the Permian Sandstone Gas Reservoirs,Ordos Basin显示文摘Objective It has long been controversial that whether authigenic chlorite coatings in sandstone reservoirs can prevent precipitation of siliceous cements.It is commonly believed that chlorite coatings(also called chlorite films,chlorite linings,or chlorite rims)may prevent quartz overgrowth,and thus help the preservation of original pores in sandstone reservoirs.Recently,however,this assumption has been challenged by reservoir geologists.This dispute cannot be solved by mere analysis of thin sections,nor by chemical equations and diagenesis analysis.The main objective of the present contribution is to shed light onFAN Aiping YANG Renchao LI Jinbu ZHAO Zhongjun A.J.(Tom) VAN LOON 2017Acta Geologica Sinica(English Edition)2017,91,3:5
7In Situ Synthesis of Fluorescent Mesoporous Silica–Carbon Dot Nanohybrids Featuring Folate Receptor-Overexpressing Cancer Cell Targeting and Drug Delivery显示文摘Multifunctional nanocarrier-based theranostics is supposed to overcome some key problems in cancer treatment.In this work,a novel method for the preparation of a fluorescent mesoporous silica–carbon dot nanohybrid was developed.Carbon dots(CDs),from folic acid as the raw material,were prepared in situ and anchored on the surface of amino-modified mesoporous silica nanoparticles(MSNs–NH2) via a microwave-assisted solvothermal reaction.The as-prepared nanohybrid(designated MSNs–CDs) not only exhibited strong and stable yellow emission but also preserved the unique features of MSNs(e.g.,mesoporous structure,large specific surface area,and good biocompatibility),demonstrating a potential capability for fluorescence imagingguided drug delivery.More interestingly,the MSNs–CDs nanohybrid was able to selectively target folate receptor-overexpressing cancer cells(e.g.,HeLa),indicating that folic acid still retained its function even after undergoing the solvothermal reaction.Benefited by these excellent properties,the fluorescent MSNs–CDs nanohybrid can be employed as a fluorescence-guided nanocarrier for the targeted deliveryof anticancer drugs(e.g.,doxorubicin),thereby enhancing chemotherapeutic efficacy and reducing side effects.Our studies may provide a facile strategy for the fabrication of multifunctional MSN-based theranostic platforms,which is beneficial in the diagnosis and therapy of cancers in future.Shuai Zhao Shan Sun Kai Jiang Yuhui Wang Yu Liu Song Wu Zhongjun Li Qinghai Shu Hengwei Lin 2019Nano-Micro Letters2019,11,2:5
8Diagonal-symmetrical and Midline-symmetrical Unit Cells with Same Porosity for Bone Implant: Mechanical Properties Evaluation显示文摘In this study, mechanical properties of bionic porous structures with diagonal-symmetrical and midline-symmetrical unit cells were studied when the porosities were same. Three typical unit cells (Diamond (DO), Rhombic Dodecahedron (RD), and Octet Truss (OT)) were selected, in which DO has diagonal-symmetrical shape, while RD and OT share midline-symmetrical structure. Based on the same porosity, corresponding models were designed, and Ti6Al4V samples were manufactured by electron beam melting. Then, using Mechanical Properties Testing (MPT) and Finite Element Analysis (FEA) methodologies, mechanical properties and transmissions of different porous structures were evaluated. Besides, composition and details before and after printing were analyzed with Energy Dispersive Spectrometer (EDS), X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). MPT results showed that midline-symmetrical shape would have superior compressive performance than diagonal-symmetrical shape, but opposite trend for the torsion performance, which were in line with FEA prediction. Furthermore, effective modulus of DO, RD and OT were 2.59 GPa, 4.89 GPa, and 1.77 GPa, approximating the mechanical properties of human bones. Additionally, manufacturing defects and discrepancies between FEA and MPT were found. This study would provide great helps for unit cell selection and initial mechanical properties matching for optimum bone implants.Jian Li Diansheng Chen Yingying Zhang Yan Yao Zhongjun Mo Lizhen Wang Yubo Fan 2019Journal of Bionic Engineering2019,16,3:4
9Green and Near-Infrared Dual-Mode Afterglow of Carbon Dots and Their Applications for Confidential Information Readout显示文摘Near-infrared(NIR),particularly NIR-containing dual-/multimode afterglow,is very attractive in many fields of application,but it is still a great challenge to achieve such property of materials. Herein,we report a facile method to prepare green and NIR dual-mode afterglow of carbon dots(CDs) through in situ embedding o-CDs(being prepared from o-phenylenediamine) into cyanuric acid(CA) matrix(named o-CDs@CA). Further studies reveal that the green and NIR afterglows of o-CDs@CA originate from thermal activated delayed fluorescence(TADF) and room temperature phosphorescence(RTP) of o-CDs,respectively. In addition,the formation of covalent bonds between o-CDs and CA,and the presence of multiple fixation and rigid e ects to the triplet states of o-CDs are confirmed to be critical for activating the observed dual-mode afterglow. Due to the shorter lifetime and insensitiveness to human vision of the NIR RTP of o-CDs@CA,it is completely covered by the green TADF during directly observing. The NIR RTP signal,however,can be readily captured if an optical filter(cut-o wavelength of 600 nm) being used. By utilizing these unique features,the applications of o-CDs@CA in anti-counterfeiting and information encryption have been demonstrated with great confidentiality. Finally,the as-developed method was confirmed to be applicable to many other kinds of CDs for achieving or enhancing their afterglow performances.Yuci Wang Kai Jiang Jiaren Du Licheng Zheng Yike Li Zhongjun Li Hengwei Lin 2021Nano-Micro Letters2021,13,12:4
10Enabling robust and hour-level organic long persistent luminescence from carbon dots by covalent fixation显示文摘The first carbon dot(CD)-based organic long persistent luminescence(OLPL)system exhibiting more than 1 h of duration was developed.In contrast to the established OLPL systems,herein,the reported CDs-based system(named m-CDs@CA)can be facilely and effectively fabricated using a household microwave oven,and more impressively,its LPL can be observed under ambient conditions and even in aqueous media.XRD and TEM characterizations,afterglow decay,time-resolved spectroscopy,and ESR analysis were performed,showing the successful composition of CDs and.CA,the formation of exciplexes and long-lived charged-separated states.Further studies suggest that the production of covalent bonds between CA and CDs plays pivotal roles in activating LPL and preventing its quenching from oxygen and water.To the best of our knowledge,this is a very rare example of an OLPL system that exhibits hourlevel afterglow under ambient conditions.Finally,applications of m-CDs@C.A in glow-in-the-dark paints for emergency signs and multicolored luminous pearls were preliminarily demonstrated.This work may provide new insights for the development of rare earth-free and robust OLPL materials.Kai Jiang Yuci Wang Cunjian Lin Licheng Zheng Jiaren Du Yixi Zhuang Rongjun Xie Zhongjun Li Hengwei Lin 2022Light(Science & Applications)2022,11,4:3
11Black phosphorus-based photothermal therapy with aCD47-mediated immune checkpoint blockade for enhanced cancer immunotherapy显示文摘Here,we describe a combination strategy of black phosphorus(BP)-based photothermal therapy together with anti-CD47 antibody(aCD47)-based immunotherapy to synergistically enhance cancer treatment.Tumour resistance to immune checkpoint blockades in most cancers due to immune escape from host surveillance,along with the initiation of metastasis through immunosuppressive cells in the tumour microenvironment,remains a significant challenge for cancer immunotherapy.aCD47,an agent for CD47/SIRPαaxis blockade,induces modest phagocytic activity and a low response rate for monotherapy,resulting in failures in clinical trials.We showed that BP-mediated ablation of tumours through photothermal effects could serve as an effective strategy for specific immunological stimulation,improving the inherently poor immunogenicity of tumours,which is particularly useful for enhancing cancer immunotherapy.BP in combination with aCD47 blockade activates both innate and adaptive immunities and promotes local and systemic anticancer immune responses,thus offering a synergistically enhanced effect in suppression of tumour progression and in inducing abscopal effects for inhibition of metastatic cancers.Our combination strategy provides a promising platform in which photothermal agents could help to enhance the therapeutic efficacy of immunotherapy.Zhongjian Xie Minhua Peng Ruitao Lu Xiangying Meng Weiyuan Liang Zhongjun Li Meng Qiu Bin Zhang Guohui Nie Ni Xie Han Zhang Paras N.Prasad 2020Light(Science & Applications)2020,9,1:3
12Osteoporosis affects both post-yield microdamage accumulation and plasticity degradation in vertebra of ovariectomized rats显示文摘Estrogen withdrawal in postmenopausal women increases bone loss and bone fragility in the vertebra. Bone loss with osteoporosis not only reduces bone mineral density(BMD), but actually alters bone quality, which can be comprehensively represented by bone post-yield behaviors. This study aimed to provide some information as to how osteoporosis induced by estrogen depletion could influence the evolution of post-yield microdamage accumulation and plastic deformation in vertebral bodies. This study also tried to reveal the part of the mechanisms of how estrogen deficiency-induced osteoporosis would increase the bone fracture risk. A rat bilateral ovariectomy(OVX)model was used to induce osteoporosis. Progressive cyclic compression loading was developed for vertebra testing to elucidate the post-yield behaviors. BMD, bone volume fraction, stiffness degradation, and plastic deformation evolution were compared among rats raised for 5 weeks(ovx5w and sham5 w groups) and 35 weeks(ovx35w and sham35 w groups) after sham surgery and OVX. The results showedthat a higher bone loss in vertebral bodies corresponded to lower stiffness and higher plastic deformation. Thus, osteoporosis could increase the vertebral fracture risk probably through microdamage accumulation and plastic deforming degradation.Siwei Li Guodong Niu Neil X. Dong Xiaodu Wang Zhongjun Liu Chunli Song Huijie Leng 2017Acta Mechanica Sinica2017,33,2:3
13A novel extractant bis(2-ethylhexyl)((2-ethylhexylamino)methyl) phosphine oxide for cerium(Ⅳ) extraction and separation from sulfate medium显示文摘By introducing the amine group into phosphorus extractant,a novel aminophosphine compound bis(2-ethylhexyl)((2-ethylhexylamino)methyl) phosphine oxide(DEHAPO,abbreviated as A) was synthesized for the extraction of cerium(Ⅳ)(Ce(Ⅳ)) from sulfate medium(H2 SO4).The influence factors including extractant concentration,H2 SO4 concentration and temperature on the Ce(Ⅳ) extraction were investigated and discussed.It is found that the extraction ability of Ce(Ⅳ),thorium(Ⅳ)(Th(Ⅳ)) and rare earths(REs(Ⅲ))(La,Gd,Yb) decreases in sulphate medium in the following order:Ce(Ⅳ)> Th(Ⅳ)> REs(Ⅲ).The extraction process is an exothermic reaction and the thermodynamic parameters were calculated.The extracted complex of Ce(HSO4)2 SO4·A in loaded organic solution was identified by the slope methods and further proved by FT-IR spectral analysis.Stripping studies indicate that Ce(IV) can be effectively stripped from the organic phase.The results of separation factors(β) and saturation loading capacity demonstrate that DEHAPO could be used to selectively extract Ce(Ⅳ) from sulphate medium with high separation efficiency and good extraction ability.Mingxia Huang Yongmei Fu Youcai Lu Wuping Liao Zhongjun Li 2020Journal of Rare Earths2020,38,12:3
14Two-dimensional magnetic resonance neurography in neurotmesis of the left sciatic nerve A case report显示文摘Magnetic resonance neurography (MRN) is used to determine traumatic changes within nervous trunks.A 21-year-old male was treated for neurotmesis of the left sciatic nerve.At 41 days after micro-neurosurgery, two-dimensional MRN (2-D MRN) was performed with plain and contrast scans in the left injured sciatic nerve.More than 2 years after trauma, 2-D MRN images were collected to re-examine the left sciatic nerve.Results from the first 2-D MRN examination revealed a swollen left sciatic nerve.Furthermore, T1WI revealed a local nodule with slightly high intensity, and T2WI revealed hyperintensity.The nodule was significantly enhanced.Upon 2-D MRN re-examination more than 2 years after injury, the injured left sciatic nerve trunk was thinner, and the nodule margin in the left sciatic trunk was clearer.The supero-inferior diameter was enlarged by 2 mm compared with previous films.The degree of enhancement became weaker in the nodule.2-D MRN revealed continuity, traumatic neuroma, and atrophy of the injured sciatic nerves in detail.Thin-slice technique was crucial for this method, as well as fat-suppressed and blood flow-suppressed imaging.Zhongjun Hou Xiaojun Yu Xi Li Yaotang Chen 2010Neural Regeneration Research2010,5,14:2
15Nyström-based spectral clustering using airborne LiDAR point cloud data for individual tree segmentation显示文摘The spectral clustering method has notable advantages in segmentation.But the high computational complexity and time consuming limit its application in large-scale and dense airborne Light Detection and Ranging(LiDAR)point cloud data.We proposed the Nyström-based spectral clustering(NSC)algorithm to decrease the computational burden.This novel NSC method showed accurate and rapid in individual tree segmentation using point cloud data.The K-nearest neighbour-based sampling(KNNS)was proposed for the Nyström approximation of voxels to improve the efficiency.The NSC algorithm showed good performance for 32 plots in China and Europe.The overall matching rate and extraction rate of proposed algorithm reached 69%and 103%.For all trees located by Global Navigation Satellite System(GNSS)calibrated tape-measures,the tree height regression of the matching results showed an value of 0.88 and a relative root mean square error(RMSE)of 5.97%.For all trees located by GNSS calibrated total-station measures,the values were 0.89 and 4.49%.The method also showed good performance in a benchmark dataset with an improvement of 7%for the average matching rate.The results demonstrate that the proposed NSC algorithm provides an accurate individual tree segmentation and parameter estimation using airborne LiDAR point cloud data.Yong Pang Weiwei Wang Liming Du Zhongjun Zhang Xiaojun Liang Yongning Li Zuyuan Wang 2021International Journal of Digital Earth2021,14,10:2
16Tuning the nucleation and decomposition of Li2O_(2) by fluorine-doped carbon vesicles towards high performance Li-O_(2) batteries显示文摘Li-O_(2) batteries provide an attractive and potential strategy for energy conversion and storage with high specific energy densities.However,large over-potential in oxygen evolution reactions (OER) caused by the decomposition obstacles of Li_(2)O_(2) seriously impedes its electrochemical performances.Herein,a novel N,O,S and F co-doping vesicular carbon was prepared by self-template pyrolysis method and used in LiO_(2) battery to tune the nucleation and decomposition of Li_(2)O_(2).The introduction of F in the carbon matrix with suitable content can regulate the adsorption of intermediates,through which the morphology of Li_(2)O_(2) can be controlled to film,favorable to its decomposition in charge process.The cathode based on the optimized F doped carbon vesicle exhibits improved electrochemical performances including a low over-potential,large capacity and a long-term stability.Density functional theory (DFT) results show that F and C in C–F bond hasve a strong interaction to Li and O in Li_(2)O_(2),respectively,which can enhance the transfer of electrons from Li_(2)O_(2) to the carbon matrix to generate hole polaron and thus accelerate the delithiation and decomposition of Li_(2)O_(2).This work provides a new sight into understanding the mechanism of nucleation and decomposition of Li_(2)O_(2) for the development of high-performance Li-O_(2) batteries.Shiyu Ma Hongchang Yao Zhongjun Li Qingchao Liu 2022Journal of Energy Chemistry2022,31,7:2
17Soil microbial community assemblage and its seasonal variability in alpine treeline ecotone on the eastern Qinghai-Tibet Plateau显示文摘The alpine treeline ecotone is characterized as the upper limit of the forest in the high-mountain ecosystem.Due to the freeze-thaw cycles,the soil organism community,such as microbial communities are expected to change between seasons.However,there are limited microbialcommunity studies focused on the high altitude alpine ecosystem.We conducted a study in the alpine treeline ecotone on the eastern Qinghai-Tibet Plateau,China,and investigated the seasonal variability of the soil microbial community.We collected all soil samples within the alpine treeline ecotone,between the treeline and timberline in the high-mountain region.The 16S rRNA genes of the microbial communities(bacterial and archaeal)were analyzed by highthroughput sequencing to the genus level.The results showed that soil microbial community in the alpine treeline ecotone was consistently dominated by eight phyla which consisted of 95% of the total microbial community,including Proteobacteria,Actinobacteria,Acidobacteria,Firmicutes,Planctomycetes,Chloroflexi,Bacteroidetes,and Verrucomicrobia.The overall diversity and evenness of the community were relatively stable,with an average of 0.5% difference between seasons.The highest seasonal variability occurred at the upper boundary of the alpine treeline ecotone,and few or almost no seasonal change was observed at lower elevations,indicating dense forest cover and litter deposition might have created a local microclimate that reduced seasonal variation among the surrounding environmental conditions.Our study was one of the first group that documented the microbial community assemblage in the treeline ecotone on the Qinghai-Tibet Plateau.Li Kui Hui Sun Qian Lei Wei Gao Lijun Bao Yuexi Chen Zhongjun Jia 2019Soil Ecology Letters2019,1,1:2
18Seat tightness of pneumatic cryogenic control valve显示文摘Pneumatic cryogenic control valves(PCCV)are designed to meet the special requirements for the large cryogenic helium refrigeration system.Polychlorotrifluoroethylene(PCTFE)is adopted as the flat seal material of the valve seat.The leakage rates and compressive strain of the PCTFE gasket with different sealing stress are tested at both room temperature(293 K)and liquid nitrogen temperature(77 K).After 300 open/close cycles,the experimental results show that the sealing properties of the PCTFE gasket are improved.The leakage rates are about 10-8(293 K)and 10-4(77 K)Pam3 s-1 respectively.Finally,the effects of working pressure on sealing characteristics are discussed.The working pressure has little effect on compressive strain but it has a great influence on leakage rate.The leakage rate is linear with the working pressure of inlet at room temperature,but at liquid nitrogen temperature the leakage rate is linear with the square of the working pressure.ZHANG Ning LI Qiang LI Qing HU ZhongJun HU Kang 2013Science China(Technological Sciences)2013,56,8:2
19Photoreceptive reaction spectrum effect and phototactic activity intensity of locusts’ visual display characteristics stimulated by spectral light显示文摘To reveal the nature of locusts’visual reaction when stimulated by light,and to clarify the regulation characteristics of locusts’phototactic visual physiology and obtain good spectral light features for locusts’phototactic action,this study investigated locusts’visual spectrum response by characterizing their photoreceptive reaction to LED light using an AvaSpec fiber-optic spectrometer system.Locusts’phototactic response to spectral light was compared using this system.The results showed that locusts’visual reaction characterization presents a photo-induced vision spectrum effect and that by offsetting the main wavelength of light and the spectral peak intensity,a time-varying bio-regulation effect emerges.In addition,locusts’visual regulation ability to UV light is higher than that to violet light,whereas their reaction intensity is lower than to violet light,and the visual bio-regulatory force of locusts’visual system absorbing orange light to react sensitively becomes gradually higher than when absorbing green light as time goes on.Moreover,corresponding to nominal illumination with the same radiant energy and a visual spectrum response stimulated by UV,violet,orange,and green light,it appears that the visual spectrum window is symmetrical around 382 nm,400 nm,602 nm,and 530 nm,respectively,with no significant difference between spectral amplitudes and having a time-varying incremental characteristic with amplitude peak width.This indicates that the stimulus intensity of UV,violet,orange,and green light exceeds locusts’visual tolerance,causing them to generate regulation inactivation as a visual physiological reaction,whereas the visual window response effect stimulated by UV light presents an illumination timeliness effect.Simultaneously,time-varying characteristics of locusts’bio-behavior intensity show that light intensity can make up for locusts’visual sensitivity differences at various spectral wavelengths.Presented with differential response time,photosensitive behavior intensity,and induction effect induced by orange light,time is superior for orange light,the stimulation effect caused by violet light is the strongest,and the phototactic synergy effect caused by UV light is the best.Qihang Liu Yueli Jiang Jin Miao Zhongjun Gong Tong Li Yun Duan Yuqing Wu 2021International Journal of Agricultural and Biological Engineering2021,14,2:2
20Dialkyl phosphinic acids: synthesis and applications as extraction for nickel and cobalt separation 显示文摘Li Linyan Xu Shengming Ju Zhongjun 2010Transactions of Nonferrous Metals Soeiety of China2010,20,1:1
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