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| 1 | aunalysis of the Genome Sequence of the Medicinal Plant Salvia miltiorrhiza显示文摘 | Haibin Xu Jingyuan Song Hongmei Luo Yujun Zhang Qiushi Li Yingjie Zhu Jiang Xu Ying Li Chi Song Bo Wang Wei Sun Guoan Shen Xin Zhang Jun Qian Aijia Ji Zhichao Xu Xiang Luo Liu He Chuyuan Li Chao Sun Haixia Yah Guanghong Cui Xiwen Li Xian 'en Li Jianhe Wei Juyan Liu Yitao Wang Alice Hayward David Nelson Zemin Ning Reuben J. Peters Xiaoquan Qi Shilin Chen | 2016 | Molecular Plant2016，9，6： | 70 |
| 2 | Paleoproterozoic crustal evolution of the Hengshan-Wutai—Fuping region,North China Craton显示文摘An arguable point regarding the Neoarchean and Paleoproterozoic crustal evolution of the North China Craton(NCC)is whether the tectonic setting in the central belt during the mid-Paleoproterozoic(2.35-2.0 Ga)was dominated by an extensional regime or an oceanic subduction-arc regime.A review of the midPaleoproterozoic magmatism and sedimentation for the Hengshan-Wutai-Fuping region suggests that a back-arc extension regime was dominant in this region.This conclusion is consistent with the observation that the 2.35-2.0 Ga magmatism shows a typical bimodal distribution where the mafic rocks mostly have arc affinities and the acidic rocks mainly comprise highly-fractioned calc-alkaline to alkaline(or A-type)granites,and that this magmatism was coeval with development of extensional basins characteristic of transgressive sequences with volcanic interlayers such as in the Hutuo Group.Although the final amalgamation of the NCC was believed to occur at ~1.85 Ga,recent zircon U-Pb age dating for mica schist in the Wutai Group suggests a collisional event may have occurred at ~1.95 Ga.The metamorphic ages of ~1.85 Ga,obtained mostly from the high-grade rocks using the zircon U-Pb approach,most probably indicate uplifting and cooling of these high-grade terranes.This is because(i)phase modeling suggests that newly-grown zircon grains in highgrade rocks with a melt phase cannot date the age of peak pressure and temperature stages,but the age of melt crystallization in cooling stages;(ii)the metamorphic P-T paths with isobaric cooling under 6-7 kb for the Hengshan and Fuping granulites suggest their prolonged stay in the middle-lower crust;and(iii)the obtained metamorphic age data show a continuous distribution from 1.95 to 1.80 Ga.Thus,an alternative tectonic scenario for the Hengshan-Wutai-Fuping region involves:(i)formation of a proto-NCC at ~2.5 Ga;(ii)back-arc extension during 2.35-2.0 Ga resulting in bimodal magmatism and sedimentation in rifting basins on an Archean basement;(iii)a crustal thickening event in the extended region resulting in a kyanitetype metamorphism at ~1.95 Ga,and(iv) uplifting and cooling of the thickened crust from 1.93 to 1.80 Ga. | Chunjing Wei Jiahui Qian Xiwen Zhou | 2014 | Geoscience Frontiers2014，5，4： | 32 |
| 3 | Design and indoor simulated experiment of pneumatic rice seed metering device显示文摘In order to meet the agronomy demand for hybrid rice direct seeding,a novel precise pneumatic rice seed metering device was designed with groups of sucking holes plate,by which 3-4 seeds could be synchronously sucked and synchronously dropped into the paddy field.The plate was divided into five sections:seed sucking,seed clearing,seed carrying,seed dropping,and blank sections.The seeds were sucked in sucking section by the vacuum,carried and rotated to the dropping section with the plate,blown away in dropping section by the positive pressure air,and thrown into the dropping tube.The influences of the hole diameter,vacuum degree,and clear-up equipment on precision of metering device were discussed.Experiments were conducted to investigate the seeding precision and simulate the field emergence rates on the indoor seeding test-bed.The subjects were pregnant Indic hybrid Peizataifeng under two kinds of moisture content(23.43%and 26.07%).Other experiment conditions included the vacuum degree of 2.60 kPa,the rotation speed of seed sucking plate of 30 r/min,three sucking holes with a diameter of 1.6 mm,and the seed layer thickness of 25 mm.The seeding results showed that,in condition of no more than two seeds per hill,the emergence probabilities under the two moisture contents were 11.82%and 11.95%,respectively,and in condition of 3-4 seeds per hill,the results were 64.81%and 65.84%,respectively.With 2-5 seeds per hill,the results were 92.08%and 92.60%,respectively.If the emergence probability was 80%,under the two moisture contents,the no seed per hill probabilities were 1.33%and 0.80%respectively;the probabilities with 3-4 seeds per hill were 56.13%and 56.40%respectively;the probabilities with 5 or more seeds per hill were 10.67%and 10.13%respectively;the probabilities with 2-5 seeds per hill were 87.60%and 88.13%respectively.The results showed the simulated experiment was an efficient and economic method to assess the capability of pneumatic rice seed drilling metering device,and the precise pneumatic rice seed drilling metering device had a good prospect in practical application. | Zhang Guozhong Zang Ying Luo Xiwen Wang Zaiman Zhang Qiang Zhang Shasha | 2015 | International Journal of Agricultural and Biological Engineering2015，8，4： | 19 |
| 4 | Complete chloroplast genome sequence of Magnolia grandiflora and comparative analysis with related species显示文摘Magnolia grandiflora is an important medicinal,ornamental and horticultural plant species.The chloroplast(cp) genome of M.grandiflora was sequenced using a 454 sequencing platform and the genome structure was compared with other related species.The complete cp genome of M.grandiflora was 159623 bp in length and contained a pair of inverted repeats(IR) of 26563 bp separated by large and small single copy(LSC,SSC) regions of 87757 and 18740 bp,respectively.A total of 129 genes were successfully annotated,18 of which included introns.The identity,number and GC content of M.grandiflora cp genes were similar to those of other Magnoliaceae species genomes.Analysis revealed 218 simple sequence repeat(SSR) loci,most composed of A or T,contributing to a bias in base composition.The types and abundances of repeat units in Magnoliaceae species were relatively conserved and these loci will be useful for developing M.grandiflora cp genome vectors.In addition,results indicated that the cp genome size in Magnoliaceae species and the position of the IR border were closely related to the length of the ycf1 gene.Phylogenetic analyses based on 66 shared genes from 30 species using maximum parsimony(MP) and maximum likelihood(ML) methods provided strong support for the phylogenetic position of Magnolia.The availability of the complete cp genome sequence of M.grandiflora provides valuable information for breeding of desirable varieties,cp genetic engineering,developing useful molecular markers and phylogenetic analyses in Magnoliaceae. | LI XiWen GAO HuanHuan WANG YiTao SONG JingYuan HENRY Robert WU HeZhen HU ZhiGang YAO Hui LUO HongMei LUO Kun PAN HongLin CHEN ShiLin | 2013 | Science China(Life Sciences)2013，56，2： | 17 |
| 5 | Characteristics and recent trends of sulfur dioxide at urban,rural,and background sites in North China:Effectiveness of control measures显示文摘SO 2 measurements made in recent years at sites in Beijing and its surrounding areas are performed to study the variations and trends of surface SO 2 at different types of sites in Northern China.The overall average concentrations of SO 2 are (16.8±13.1) ppb,(14.8±9.4) ppb,and (7.5±4.0) ppb at China Meteorological Administration (CMA,Beijing urban area),Gucheng (GCH,relatively polluted rural area,110 km to the southwest of Beijing urban area),and Shangdianzi (SDZ,clean background area,100 km to the northeast of Beijing urban area),respectively.The SO 2 levels in winter (heating season) are 4-6 folds higher than those in summer.There are highly significant correlations among the daily means of SO 2 at different sites,indicating regional characteristics of SO 2 pollution.Diurnal patterns of surface SO 2 at all sites have a common feature with a daytime peak,which is probably caused by the downward mixing and/or the advection transport of SO 2 -richer air over the North China Plain.The concentrations of SO 2 at CMA and GCH show highly significant downward trends (-4.4 ppb/yr for CMA and -2.4 ppb/yr for GCH),while a less significant trend (-0.3 ppb/yr) is identified in the data from SDZ,reflecting the character of SDZ as a regional atmospheric background site in North China.The SO 2 concentrations of all three sites show a significant decrease from period before to after the control measures for the 2008 Olympic Games,suggesting that the SO 2 pollution control has long-term effectiveness and benefits.In the post-Olympics period,the mean concentrations of SO 2 at CMA,GCH,and SDZ are (14.3±11.0) ppb,(12.1±7.7) ppb,and (7.5±4.0) ppb,respectively,with reductions of 26%,36%,and 13%,respectively,compared to the levels before.Detailed analysis shows that the differences of temperature,relative humidity,wind speed,and wind direction were not the dominant factors for the significant differences of SO 2 between the pre-Olympics and post-Olympics periods.By extracting the data being more representative of local or regional characteristics,a reduction of up to 40% for SO 2 in polluted areas and a reduction of 20% for regional SO 2 are obtained for the effect of control measures implemented for the Olympic Games. | Weili Lin Xiaobin XU Zhiqiang Ma Huarong Zhao Xiwen Liu Ying Wang | 2012 | Journal of Environmental Sciences2012，24，1： | 15 |
| 6 | Kinetics of the accumulation of group 2 innate lymphoid cells in IL-33-induced and IL-25-induced murine models of asthma:a potential role for the chemokine CXCL16显示文摘ILC2s are implicated in asthma pathogenesis, but little is known about the mechanisms underlying their accumulation in airways.We investigated the time course of ILC2 accumulation in different tissues in murine models of asthma induced by a serial per-nasalchallenge with ovalbumin (OVA), house dust mice (HDM), IL-25 and IL-33 and explored the potential roles of ILC2-attractingchemokines in this phenomenon. Flow cytometry was used to enumerate ILC2s at various time points. The effects of cytokines andchemokines on ILC2 migration were measured in vitro using a chemotaxis assay and in vivo using small animal imaging. Comparedwith saline and OVA challenge, both IL-25 and IL-33 challenge alone induced significant accumulation of ILC2s in the mediastinallymph nodes, lung tissue and bronchoalveolar lavage fluid of challenged animals, but with a distinct potency and kinetics. In vitro,IL-33 and CXCL16, but not IL-25 or CCL25, directly induced ILC2 migration. Small animal in vivo imaging further confirmed that asingle intranasal provocation with IL-33 or CXCL16 was sufficient to induce the accumulation of ILC2s in the lungs followinginjection via the tail vein. Moreover, IL-33-induced ILC2 migration involved the activation of ERK1/2, p38, Akt, JNK and NF-κB, whileCXCL16-induced ILC2 migration involved the activation of ERK1/2, p38 and Akt. These data support the hypothesis that epitheliumderived IL-25 and IL-33 induce lung accumulation of ILC2s, while IL-33 exerts a direct chemotactic effect in this process. AlthoughILC2s express the chemokine receptors CXCR6 and CCR9, only CXCL16, the ligand of CXCR6, exhibits a direct chemoattractanteffect. | Yan Li Shihao Chen Yafei Chi Yiran Yang Xiwen Chen Huating Wang Zhe Lv Jingjing Wang Linjie Yuan Ping Huang Kewu Huang Chris JCorrigan Wei Wang Sun Ying | 2019 | Cellular & Molecular Immunology2019，16，1： | 13 |
| 7 | 1996年中国艾滋病哨点监测报告显示文摘我国自1995年开始在23个省(自治区、直辖市)的42个哨点中对性传播疾病(STDs)门诊就诊者、暗娼、吸毒者和长途卡车司机四类人群进行监测,当年监测结果显示,在监测哨点所在的城市中,被监测的STDs门诊就诊者、暗娼、吸毒者和长途卡车司机人群中HIV感染率均很低,但存在广泛传播的危险性。1996年第一轮共监测10085人,发现HIV感染者35例。其中在STDs门诊就诊者中发现HIV感染者1例,在吸毒者中发现HIV感染者34例(其中新疆32例);第二轮监测11909人,发现HIV感染者72例,其中在暗娼人群中发现1例,在吸毒人群中发现71例(其中新疆69例)。1996年监测结果表明,在哨点所在的城市中,尽管被监测的STDs门诊就诊者、暗娼和长途卡车司机人群中HIV感染率仍很低,但我国HIV流行形势已发生改变,HIV感染的流行已不仅仅局限于云南吸毒者中,在其它地区已开始在吸毒者中流行,个别地区该人群中HIV感染率上升很快。 | Department of Disease control.Ministry of Health,People′s Republic of China 1 Center for AIDS Surveillance,Chinese Academy of Preventive Medicine 2 Group of National HIV sentinel surveillance program (Written by Qu Shuquan 2,Sun Xinhua 1,Zheng Xiwen | 1997 | 中国性病艾滋病防治1997，3，5： | 12 |
| 8 | ACPAs promote IL-1β production in rheumatoid arthritis by activating the NLRP3 inflammasome显示文摘OBJECTIVES:Anti-citrullinated protein antibodies(ACPAs)are a group of autoantibodies targeted against citrullinated proteins/peptides and are informative rheumatoid arthritis(RA)biomarkers.ACPAs also play a crucial role in RA pathogenesis,and their underlying mechanism merits investigation.METHODS:Immunohistochemical(IHC)assays were carried out to determine IL-1βlevels in ACPA+and ACPA−RA patients.PBMCderived monocytes were differentiated into macrophages before stimulation with ACPAs purified from RA patients.The localization and interaction of molecules were analyzed by confocal microscopy,co-IP,and surface plasmon resonance.RESULTS:In our study,we found that IL-1βlevels were elevated in ACPA+RA patients and that ACPAs promoted IL-1βproduction by PBMC-derived macrophages.ACPAs interacted with CD147 to enhance the interaction between CD147 and integrinβ1 and,in turn,activate the Akt/NF-κB signaling pathway.The nuclear localization of p65 promoted the expression of NLRP3 and pro-IL-1β,resulting in priming.Moreover,ACPA stimulation activated pannexin channels,leading to ATP release.The accumulated ATP bound to the P2X7 receptor,leading to NLRP3 inflammasome activation.CONCLUSIONS:Our study suggests a new hypothesis regarding IL-1βproduction in RA involving ACPAs,which may be a potential therapeutic target in RA treatment. | Xiwen Dong Zhaohui Zheng Peng Lin Xianghui Fu Fanni Li Jianli Jiang Ping Zhu | 2020 | Cellular & Molecular Immunology2020，17，3： | 11 |
| 9 | Analysis of the severe group dust storms in eastern part of Northwest China显示文摘Based on the available original dust storm records from 60 meteorological stations, we discussed the identification standard of severe dust storms at a single station and constructed a quite complete time series of severe group dust storms in the eastern part of Northwest China in 1954-2001.The result shows that there were 99 severe group dust storms in this region in recent 48 years. The spatial distribution indicates that the Alax Plateau, most parts of the Ordos Plateau and most parts of the Hexi Corridor are the main areas influenced by severe group dust storms. In addition, the seasonand the month with the most frequent severe group dust storms are spring and April, accounting for 78.8% and 41.4% of the total events respectively. During the past 48 years the lowest rate of severe group dust storms occurred in the 1990s. Compared with the other 4 decades, on the average, the duration and the affected area of severe group dust storms are relatively short and small during the 1990s. In 2000 and 2001, there were separately 4 severe group dust storms as the higher value after 1983 in the eastern part of Northwest China. | ZHOU Zijiang, WANG Xiwen(1. National Meteorological Center, Beijing 100081, China 2. Lanzhou Central MeteorologicalObservatory, Lanzhou 730020, China) | 2002 | Journal of Geographical Sciences2002，12，3： | 10 |
| 10 | General structure design and field experiment of pneumatic rice direct-seeder显示文摘In order to meet the requirement of field direct seeding for super hybrid rice:1-3 seeds per hill,a pneumatic rice direct-seeder with six seeding metering devices was designed.Transmission system of pneumatic rice direct-seeder and seed metering device were analyzed in this study.And the pipeline structure and vortex pump were designed and selected.The pressure distribution of the pipeline was tested.The pressure value of each sub-pipeline under the conditions of different main pipeline pressure value was obtained and the reasons for pressure loss were analyzed.The results showed that the variation coefficient between sub-pipelines was less than 5%.The pipeline pressure could be evenly distributed.Further,the field experiments were carried out on super hybrid rice Peizataifeng using two-factor testing,by which the effects of different negative pressure and different forward speed(namely,rotational speed of suction plate)for seeding precision were studied.It found that:(1)the optimal negative pressure was 2 kPa;(2)under the optimal negative pressure,the probabilities of 1-3 seeds per hill for the direct-seeder were 93.41%,95.47%and 97.50%,respectively,when the forward speed of the direct-seeded was high,medium and low speed;(3)the probability of empty hole was less than 2%,which satisfied the field direct seeding requirements of super hybrid rice.Additionally,hill spacing was measured,and the factors affecting the hill spacing were analyzed.The results showed that the fluctuation of hill spacing in the small range will not affect the seeding effect.In this study,a new type of pneumatic rice direct-seeder was designed.The main working components were tested and analyzed.The best parameters of field work were obtained.It provides the basis for the field application of the pneumatic rice precision seeder. | Xing He Wang Zaiman Luo Xiwen Cao Xiaoman Liu Chunbo Zang Ying | 2017 | International Journal of Agricultural and Biological Engineering2017，10，6： | 10 |
| 11 | Study of dynamic hydrophobicity of micro-structured hydrophobic surfaces and lotus leaves显示文摘The dynamic wetting characteristics of water droplets on silicon wafers with microscale regular pillars structures and fresh lotus leaves are investigated experimentally.We measured the static contact angle,contact angle hysteresis,and roll-off angle of water droplets on both of these superhydrophobic surfaces with a high speed contact angle meter.The dynamic contact angles and internal velocity distribution of water droplets on superhydrophobic surfaces were studied with a high-speed camera system and a particle image velocimetry (PIV) system,respectively.We found that the acceleration of water droplets when they slide off lotus leaves is greater than that of water droplets sliding off the silicon wafers with microscale pillar structures although the static contact angles of water droplets on lotus leaves are slightly smaller than those on the silicon wafers.The reason is that water droplets sliding off lotus leaves have smaller contact angle hysteresis and larger slip velocities.These results indicate that the dynamic contact angle hysteresis and sliding acceleration of liquid droplets are more suitable for reflecting the hydrophobicity of material surfaces compared with static contact angles.Our experiments also show that lotus leaves with multiscale micro/nanostructures have stronger hydrophobicity and self-cleaning properties compared with the micro-structured superhydrophobic surfaces. | HAO PengFei YAO ZhaoHui ZHANG XiWen | 2011 | Science China(Physics,Mechanics & Astronomy)2011，54，4： | 10 |
| 12 | Designing N-doped graphene/ReSe_(2)/Ti_(3)C_(2) MXene heterostructure frameworks as promising anodes for high-rate potassium-ion batteries显示文摘Developing high-performance anodes for potassium ion batteries(KIBs) is of paramount significance but remains challenging.In the normal sense,electrode materials are prepared by ubiquitous wet chemical routes,which otherwise might not be versatile enough to create desired heterostructures and/or form clean interfacial areas for fast transport of K-ions and electrons.Along this line,rate capability/cycling stability of resulting KIBs are greatly handicapped.Herein we present an all-chemical vapor deposition approach to harness the direct synthesis of nitrogen-doped graphene(NG)/rhenium diselenide(ReSe_2)hybrids over three-dimensional MXene supports as superior heterostructure anode material for KIBs.In such an innovative design,1 T'-ReSe2 nanoparticles are sandwiched in between the NG coatings and MXene frameworks via strong interfacial interactions,thereby affording facile K~+ diffusion,enhancing overall conductivity,boosting high-power performance and reinforcing structural stability of electrodes.Thus-constructed anode delivers an excellent rate performance of 138 mAh g^(-1) at 10.0 A g^(-1) and a high reversible capacity of 90 mAh g^(-1) at 5 A g^(-1) after 300 cycles.Furthermore,the potassium storage mechanism has been systematically probed by advanced in situlex situ characterization techniques in combination with first principles computations. | Zhou Xia Xiwen Chen Haina Cia Zhaodi Fan Yuyang Yi Wanjian Yin Nan Wei Jingsheng Cai Yanfeng Zhang Jingyu Sun | 2021 | Journal of Energy Chemistry2021，30，2： | 9 |
| 13 | Synthesis,characterization and catalytic properties of Y-β zeolite composites显示文摘Y-β zeolite composites were hydrothermally synthesized by using high silica Y zeolite as the precursor and characterized by XRD,N2 adsorption,SEM and IR spectra of pyridine.The result showed that the N2 adsorption-desorption isotherm of the zeolite composites had a distinct hysteresis loop,and the SEM result showed that the zeolite composites had a different morphology from Y,β and the corresponding physical zeolite mixture.The acid catalytic performance of the zeolite composite catalysts was investigated in the hydrocracking and hydroisomerization of n-octane,and the results showed that the composite materials exhibited an excellent hydrocracking activity and good hydroisomerization performance.The yield of i-C4 over the zeolite composite catalyst was 4.45% higher than that on the corresponding zeolite mixture in the n-octane hydrocracking process at 553 K.The isomerization ability of n-octane over the composite catalyst was 3.6 fold that of the corresponding mixture at 503 K. | Qin Bo Zhang Xiwen Zhang Zhizhi Ling Fengxiang Sun Wanfu | 2011 | Petroleum Science2011，8，2： | 9 |
| 14 | Asymmetric encryption and signature method with DNA technology显示文摘This paper proposes DNA-PKC, an asymmetric encryption and signature cryptosystem by combining the technologies of genetic engineering and cryptology. It is an exploratory research of biological cryptology. Similar to conventional public-key cryptology, DNA-PKC uses two pairs of keys for encryption and signature, respectively. Using the public encryption key, everyone can send encrypted message to a specified user, only the owner of the private decryption key can decrypt the ciphertext and recover the message; in the signature scheme, the owner of the private signing key can generate a signature that can be verified by other users with the public verification key, but no else can forge the signature. DNA-PKC differs from the conventional cryptology in that the keys and the ciphertexts are all biological molecules. The security of DNA-PKC relies on diffcult biological problems instead of computational problems; thus DNA-PKC is immune from known attacks, especially the quantum computing based attacks. | LAI XueJia LU MingXin QIN Lei HAN JunSong FANG XiWen | 2010 | Science China(Information Sciences)2010，53，3： | 9 |
| 15 | Preparation of novel bovine hemoglobin surface-imprinted polystyrene nanoparticles with magnetic susceptibility显示文摘In this research, a surface imprinting strategy has been adopted in protein imprinting. Bovine hemo-globin surface-imprinted polystyrene (PS) nanoparticles with magnetic susceptibility have been syn-thesized through multistage core-shell polymerization system using 3-aminophenylboronic acid (APBA) as functional and cross-linking monomers. Superparamagnetic molecularly imprinted polystyrene nanospheres with poly(APBA) thin films have been synthesized and used for the first time for protein molecular imprinting in an aqueous solution. The magnetic susceptibility is imparted through the successful encapsulation of Fe3O4 nanoparticles. The morphology, adsorption, and recognition prop-erties of superparamagnetic molecularly imprinted polymers (MIPs) have been investigated using transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and vibrating sample magnetometer. Rebinding experimental results show that poly(APBA) MIPs-coated superparamagnetic PS nanoparticles have high adsorption capacity for template protein bovine hemoglobin and compara-tively low nonspecific adsorption. The imprinted superparamagnetic nanoparticles could easily reach the adsorption equilibrium and achieve magnetic separation in an external magnetic field, thus avoid-ing some problems of the bulk polymer. | LI Lin HE XiWen CHEN LangXing ZHANG YuKui | 2009 | Science China Chemistry2009，52，9： | 8 |
| 16 | Experimental and computational studies on the flow fields in aortic aneurysms associated with deployment of AAA stent-grafts显示文摘在僵硬腹的大动脉的动脉瘤(AAA ) 的脉动的流动地模型数字地被调查,并且模拟结果在对粒子图象 velocimetry (PIV ) 的好同意被发现大小。有至少一在 AAA 膨胀的旋涡,和一面相当高的墙砍应力在远侧的结束存在,并且这样 AAA 处于破裂的危险中。医疗由在 AAA 插入脉管的 stent 接枝组成,它将减少血影响到内部墙和还原剂墙砍强调以便破裂能被阻止。基于多孔的中等模型,一个新计算模型被开发,结果被记录。stent 接枝的治疗学的效果与新模型一起数字地被验证。 | Xiwen Zhang Zhaohui Yao Yan Zhang Shangdong Xu | 2007 | Acta Mechanica Sinica2007，23，5： | 7 |
| 17 | Properties and microstructure of VC/Cr_3C_2-doped WC/Co cemented carbides显示文摘This paper deals with the effects of codoped VC/Cr3C2 and sintering temperature on the magnetic and mechanical properties of ultra-fine grained WC-12%Co alloys. Results show that the synergistic action of doped VC/Cr3C2 in optimal proportion enhances both the hardness and transverse rupture strength (TRS) of the alloys, with more homogeneous microstructure. When the alloy is sintered at 1430°C and with 0.5% Cr3C2/0.2% VC, the TRS reaches 3786 MPa, the hardness is 91.7 HRA and the grain size smaller than 0.6 μm. The numerical analyses on grain growth during the sintering process show that both VC precipitating on the WC grain boundary and Cr3C2 dissolving in the Co phase decrease the solid/liquid interfacial energy γ, the process of dissolution and reprecipitation is greatly retarded and the coarsening of WC grains is inhibited. | LEI Yiwen SUN Jing DU Xiwen ZHAI Qi HU Shengliang | 2007 | Rare Metals2007，26，6： | 7 |
| 18 | Realization of quantum discrete Fourier transform with NMR显示文摘The pulse sequences of the logic operations used in quantum discrete Fourier transform are designed for the experiment of nuclear magnetic resonance(NMR), and 2-qubit discrete Fourier transforms are implemented experimentally with NMR. The experimental errors are examined and methods for reducing the errors are proposed. | FANG Ximing ZHU Xiwen FENG Mang MAO Xi’an DU Fei | 2000 | Chinese Science Bulletin2000，45，12： | 7 |
| 19 | Altered Neuronal Activity in the Central Nucleus of the Amygdala Induced by Restraint Water-Immersion Stress in Rats显示文摘Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress(RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition,RWIS, but not RS, induced the activation of corticotropinreleasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers.This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors. | Feng He Hongbin Ai Min Wang Xiusong Wang Xiwen Geng | 2018 | Neuroscience Bulletin2018，34，6： | 7 |
| 20 | Optimization of variables for maximizing efficacy and efficiency in aerial spray application to cotton using unmanned aerial systems显示文摘Aerial spraying can support efficient defoliation without crop contact.With the recent introduction to unmanned aerial system(UAS)for aerial spraying in China,there is a need to determine the optimum application variables to achieve high efficacy and efficiency with low costs.The present research involved field studies across two annual cotton production seasons in North Xinjiang,China.Four factors,including volume rate(A),tank mix including spray adjuvants(B),flight altitude(C),flight speed(D)and three levels of L9(3^(4))orthogonal arrays were carried out to optimize the application parameters for three types of UASs.These included different numbers of rotors as follows:four-rotors,six-rotors and eight-rotors.Spray coverage,distribution uniformity(coefficient of variation(CV)of droplet coverage),rates of cotton defoliation and boll opening,application efficiency and cost were measured and assessed.Results showed that:(1)the rates of defoliation and boll opening by aerial cotton defoliant application could meet the requirement of cotton mechanized harvesting;(2)the optimal scenario for the three UASs was A_(3)B_(2)C_(1)D_(3),Volume rate(A3):48 L/hm^(2);Tank mix and concentration(B_(2)):(Tuotulong 225+Sujie 750+Ethephon 2250)mL/hm^(2),Flight altitude(C_(1)):1.5 m,and Flight speeds(D_(3))for unmanned helicopters with four-rotors,six-rotors and eight-rotors were 3.12 m/s,2.51 m/s and 3.76 m/s,respectively.These results can provide guidance for cotton defoliant aerial spraying in China using UAS. | Juan Liao Ying Zang Xiwen Luo Zhiyan Zhou Yubin Lan Yu Zang Xiuyan Gu Weiming Xu Andrew John Hewitt | 2019 | International Journal of Agricultural and Biological Engineering2019，12，2： | 6 |
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