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1Altitudinal changes of surface pollen and vegetation on the north slope of the Middle Tianshan Mountains,China显示文摘To provide information on vegetation patterns and altitudinal distributions of pollen assemblage in surface soil layers,their complicated relationships in a dryland mountain-basin system in northwestern China and a realistic basis for paleovegetational reconstruction,we investigated 86 vegetation quadrats and analyzed 80 soil samples from the surface soil layers along an altitudinal transect on the north slope of the Middle Tianshan Mountains from alpine cushion vegetation at 3,510 m near glacier to desert vegetation at 460 m in the Gurbantunggut Desert.According to surface pollen assemblages and the results of the detrended correspondence analysis,the transect can be divided into six major altitudinal pollen zones as alpine cushion vegetation,alpine and subalpine meadows,montane Picea forest,forest-steppe ecotone,Artemisia desert and typical desert,which basically reflect the characteristics of the mountainous vegetation patterns on the north slope of the Middle Tianshan Mountains.However,Picea pollen also exists outside the spruce forest,Chenopodiaceae and Artemisia pollen appeared above the elevation of 1,300 m,indicating that most of them might be introduced from lower elevations by upslope winds.Airborne pollen researches from three regions at different elevations further suggest that a high-frequency northwest anabatic wind has a remarkable influence on the transportation and dispersion of surface pollen in the area.YANG Zhenjing ZHANG Yun REN Haibao YAN Shun KONG Zhaochen MA Keping NI Jian 2016Journal of Arid Land2016,8,5:17
2Pollen record and environmental evolution of Caotanhu wetland in Xinjiang since 4550 cal. a BP显示文摘This paper presents a multi-proxy reconstruction of the climate change in Caotanhu wetland using pollen, phytolith and charcoal records, and the data of loss of ignition (LOI), grain size analysis, and susceptibility. Results reveal that between 4550 and 2500 cal. a BP, a dry climatic condition was not favorable for the accumulation of peat. Since 2500 cal. a BP, the climate became humid and the wetland developed with abundant freshwater aquatic plants, which contributed to peat accumulation. Never-theless, alternate periods of rain and dry climate occurred during that period. Between 2500 and 1810 cal. a BP (550 BC―140 AD), the climate was more humid than at present. A lot of emerged plants, such as Phragmites, Typha and Sparganium, and freshwater green algae grew in the wetland which was sur-rounded by desert-steppe vegetation composed mainly of Chenopodiaceae, Artemisia, Compositae and Thalictrum. However, from 1810 to 1160 cal. a BP (140―790 AD), the water level started to decrease and hydrophyte species reduced greatly, but some Phragmites still grew in the wetland and around it was desert vegetation with high proportion of Chenopodiaceae and Artemisia. Then from 1160 to 650 a BP (790―1300 AD), it entered a period of desert-steppe with abundant mesic and xerophytic plants. And a lot of aquatic plants prevailed in the wetland. Here, what is noticeable is that percentages of arboreal pollen, consisting mainly of Betula and Picea, increased greatly and reached a maximal value of 27.2%, in which, Betula percentages rose to 23.2%. Hence, it is reasonable to conclude that Betula grew in the highland of the wetland, or Picea timberline shifted downward resulting in the increase of percentages of Betula and Picea pollen, which were transported into the wetland by flood or wind. But since 650 cal. a BP, desert vegetation prevailed around the wetland again with dominant Chenopodiaceae and Ar-temisia, and the climate was similar to modern one. Despite some aquatic plants still growing in the wetland at that time, their amounts diminished greatly.ZHANG Yun KONG ZhaoChen NI Jian YAN Shun YANG ZhenJing 2008Chinese Science Bulletin2008,53,7:11
3Multifunctional lymph-targeted platform based Mn@mSiO2 nanocomposites: Combining PFOB dual-mode imaging and DOX for cancer diagnose treatment on for and显示文摘Tian Liu Guangyu Wu Jiejun Cheng Qing Lu Yanjie Yao Zhenjing Liu Dongchen Zhu Juan Zhou Jianrong Xu Jun Zhu Dannong He 2016Nano Research2016,9,2:11
4Milling surface roughness for 7050 aluminum alloy cavity influenced by nozzle position of nanofluid minimum quantity lubrication显示文摘In nanofluid minimum quantity lubrication(NMQL)milling of aviation aluminum alloy,it is the bottleneck problem to adjust the position parameters(target distance,incidence angle,and elevation angle)of the nozzle to improve the surface roughness of milling,which has large and uncontrollable errors.In this paper,the influence law of milling cutter speed,helical angle,and cavity shape on the flow field around the milling cutter was studied,and the optimal nozzle profile parameters were obtained.Using 7050 aluminum alloy as the workpiece material,the milling experiment of the NMQL cavity was conducted by utilizing cottonseed oil-based Al2 O3 nanofluid.Results show that the high velocity of the surrounding air flow field and the strong gas barrier could be attributed to high rotating velocities of the milling cutter.The incidence angle of the nozzle was consistent with the helical angle of the milling cutter,the target distance was appropriate at 25–30 mm,and the elevation angle was suitable at 60°–65°.The range and variance analyses of the signal-to-noise ratio of milling force and roughness were performed,and the chip morphology was observed and analyzed.The results show that the optimal combination of nozzle position parameters was the target distance of 30 mm,the incidence angle of 35°,and the elevation angle of 60°.Among these parameters,target distance had the largest impact on cutting performance with a contribution rate of more than 55%,followed by incidence angle and elevation contribution rate.Analysis by orthogonal experiment revealed that the nozzle position parameters were appropriate,and Ra(0.087 lm)was reduced by 30.4%from the maximum value(0.125 lm).Moreover,Rsm(0.05 mm)was minimum,which was 36%lower than that of the seventh group(Rsm=0.078 mm).Zhenjing DUAN Changhe LI Yanbin ZHANG Lan DONG Xiufang BAI Min YANG Dongzhou JIA Runze LI Huajun CAO Xuefeng XU 2021Chinese Journal of Aeronautics2021,34,6:10
5Fluctuation of Picea timberline and paleoenvironment onthe northern slope of Tian-shan Mountains during the late Holocene显示文摘As a good indicator of Holocene climate, the fluctuation of alpine timberline is a synthetical result of impacts of many environmental factors dur-ing geological and historical periods and modern times. As the dominant tree species of mountainous conifer forests on the northern slope of Tianshan Mountains in Xinjiang, the distribution of Picea schrenkiana and its population size are sensitive to climatic change. The typical natural profile of Huashuwozi and the nearby Xiaoxigou archaeologi-cal profile, located in Quanzijie Township, Jimusaer County in Xinjiang, were chosen to analyze and compare the relative high-resolution pollen records, and to measure 14C dating and SEM (scanning elec-tron microscope) microstructure for charcoal frag-ments contained in Xiaoxigou profile’s cultural layers. The results show that in these two profiles, the high percentages of Picea (more than 20% and 35%, re-spectively) appeared in the stratum of the same pe-riod (2000-1300 a BP), which corresponds to the charcoal fragment’s age of Picea schrenkiana con-tained in Xiaoxigou cultural layers. These results convincingly revealed that during the period of 2000-1300 a BP, the timberline for Picea schrenkiana on the northern slope of Tianshan Mountains in Xinjiang declined by about 330m compared with the present.ZHANG Yun KONG Zhaochen YAN Shun YANG Zhenjing NI Jian 2006Chinese Science Bulletin2006,51,14:9
6Milling Force Model for Aviation Aluminum Alloy: Academic Insight and Perspective Analysis显示文摘Aluminum alloy is the main structural material of aircraft,launch vehicle,spaceship,and space station and is processed by milling.However,tool wear and vibration are the bottlenecks in the milling process of aviation aluminum alloy.The machining accuracy and surface quality of aluminum alloy milling depend on the cutting parameters,material mechanical properties,machine tools,and other parameters.In particular,milling force is the crucial factor to determine material removal and workpiece surface integrity.However,establishing the prediction model of milling force is important and difficult because milling force is the result of multiparameter coupling of process system.The research progress of cutting force model is reviewed from three modeling methods:empirical model,finite element simulation,and instantaneous milling force model.The problems of cutting force modeling are also determined.In view of these problems,the future work direction is proposed in the following four aspects:(1)high-speed milling is adopted for the thin-walled structure of large aviation with large cutting depth,which easily produces high residual stress.The residual stress should be analyzed under this particular condition.(2)Multiple factors(e.g.,eccentric swing milling parameters,lubrication conditions,tools,tool and workpiece deformation,and size effect)should be considered comprehensively when modeling instantaneous milling forces,especially for micro milling and complex surface machining.(3)The database of milling force model,including the corresponding workpiece materials,working condition,cutting tools(geometric figures and coatings),and other parameters,should be established.(4)The effect of chatter on the prediction accuracy of milling force cannot be ignored in thin-walled workpiece milling.(5)The cutting force of aviation aluminum alloy milling under the condition of minimum quantity lubrication(mql)and nanofluid mql should be predicted.Zhenjing Duan Changhe Li Wenfeng Ding Yanbin Zhang Min Yang Teng Gao Huajun Cao Xuefeng Xu Dazhong Wang Cong Mao Hao Nan Li Gupta Munish Kumar Zafar Said Sujan Debnath Muhammad Jamil Hafiz Muhammad Ali 2021Chinese Journal of Mechanical Engineering2021,34,1:7
7Maize MS2 encodes an ATP-binding cassette transporter that is essential for anther development显示文摘The anther cuticle and pollen exine play a critical role in male gametophyte development. The sporopollenin precursors and cuticular lipid monomers are transported to the surface of the microspores and the epidermis by lipid transport proteins(LTPs) and ATP-binding cassette G(ABCG) transporters for the formation of the pollen wall and anther cuticle, respectively. However, the function of ABCG transporters in maize anther development is unclear. Here, we cloned the MS2 gene from the maize male sterile2 mutant using map-based cloning and determined that it encodes an ABCG transporter. MS2 protein was experimentally confirmed to be located on the cell membrane. The quantitative real-time PCR(qRT-PCR)results showed that MS2 was ubiquitously expressed in all vegetative and reproductive tissues, whereas a high transcriptional level of MS2 was observed in anthers, especially at the young microspore stage. Gas chromatography-mass spectrometry(GC–MS) analysis showed decreased accumulation of cutin and wax components in ms2 anthers, indicating that MS2 plays a role in the transport of lipid molecules to anther cuticle and pollen exine. To our knowledge, MS2 is the first reported ABCG transporter gene that participates in anther development in maize.Qilong Xu Li Yang Dan Kang Zhenjing Ren Yunjun Liu 2021The Crop Journal2021,9,6:4
8Identification of Major Locus Bph35 Resistance to Brown Planthopper in Rice显示文摘An introgression line RBPH660,derived from wild rice Oryza rufipogon,showed stable resistance to brown planthopper(BPH).Segregation analysis indicated BPH resistance of RBPH660 was controlled by multiple genes/QTLs.By using the bulked segregant analysis(BSA)-seq method,two genomic regions harboring QTLs resistance to BPH were identified from 1.20 to 16.70 Mb on chromosome 4 and from 10.20 to 12.60 Mb on chromosome 9 in RBPH660,respectively.A major resistance locus,designated as Bph35 accounting for 51.27%of the phenotypic variation with a LOD score of 42.51,was mapped to the candidate region of chromosome 4 between In Del(insertion-deletion)markers PSM16 and R4 M13.For fine mapping of Bph35,one simple sequence repeat and three newly developed In Del markers were used to screen the recombinants.Finally,the Bph35 locus was delimited in the region from 6.28 to 6.93 Mb and there were 18 predicted protein-encoding genes with a total of 114 non-synonymous single nucleotide polymorphism(SNP)variant sites between the resistant and susceptible parents.Out of these genes,Os04 g0193950,encoding a putative NB-ARC(nucleotidebinding adaptor shared by APAF-1,R proteins and CED-4)and LRR(leucine-rich repeat)domain protein with nine non-synonymous SNP substitutions in its coding sequence regions,might be the candidate gene for Bph35.These findings would facilitate the map-based cloning of the Bph35 gene and development of resistant varieties against BPH in rice.ZHANG Yuexiong QIN Gang MA Qianqian WEI Minyi YANG Xinghai MA Zengfeng LIANG Haifu LIU Chi LI Zhenjing LIU Fang HUANG Dahui LI Rongbai 2020Rice science2020,27,3:3
9Room thermal load prediction based on analytic hierarchy process and back-propagation neural networks显示文摘Accurate prediction of the heat load is the basic premise of intelligent regulation of the heating system,which helps to realize effective management of heating,ventilation,air conditioning system.For the problem that the weight of each influencing factor is not taken into account in the current heat load prediction and is not highly targeted,this article deeply explores the influence of different factors on the room heat load,and we propose a method to calculate room heat load prediction based on the combination of analytic hierarchy process(AHP)and back-propagation(BP)neural network.Firstly,eight environmental factors affecting the heat load are selected as prediction inputs through parametric analysis,and then the weights of each input are determined by AHP and normalize the prediction data by combining expert opinions,and finally do one-to-one training the quantified score and the room heat load to predict the future heat load by BP neural network.The simulation tests show that the mean absolute relative error(MARE)of the proposed prediction method is 5.40%.This article also verifies the influence of different expert opinions on the stability of the model.The results show that the proposed method can guarantee higher prediction accuracy and stability.Xin Tan Zhenjing Zhu Guoxin Sun Linfeng Wu 2022Building Simulation2022,15,11:2
10Experimental Study on Analgesia and Hemostasis of Paris polyphylla,Scutellaria baicalensis and Their Compatibility显示文摘[Objectives]The analgesic and hemostatic effects of Paris polyphylla,Scutellaria baicalensis,and their compatibility were studied.[Methods](i)In the experiment on the writhing of mice induced by acetic acid,60 Kunming SPF mice were randomly selected,and were randomly divided into 6 groups according to the male-to-female ratio of 1∶1,including blank control group,P.polyphylla group,S.baicalensis group,and three P.polyphylla and S.baicalensis compatibility groups(with the ratio of 1∶2,1∶1 and 1∶2).There were 10 mice in each group.In the experimental groups,the mice were given 1 g/mL Chinese medicine extract according to a dose of 20 mL/kg.In the control group,the mice were given 0.9%normal saline in equal volumes.Gavage was performed one time every 24 h and lasted for 14 d.1 h after the gavage on the 14th day,they were given 0.5%glacial acetic acid solution via intraperitoneal injection.(ii)In the hot plate experiment,60 Kunming SPF mice were selected,and the ratio of male to female,grouping,administration and gavage were the same as those of the glacial acetic acid-induced writhing experiment.Gavage was lasted for 14 d.1 h after the gavage on the 14th day,the mice were placed on a hot plate apparatus at(55±0.5)℃,and the time of licking hindfoot was measured.(iii)The hemostatic effect was explored through three experimental methods of tail hemostasis,femoral artery hemostasis and liver hemostasis.60 Kunming SPF mice were taken in each of the three experiments,and the male-female ratio and grouping were the same as above.The powder was covered on the surface of the wound sites,and the bleeding was observed.The hemostatic time was recorded,and the hemostatic time was recorded as 3 min if it exceeded 3 min.[Results](i)In the acetic acid-induced writhing experiment,compared with the blank control group,the pain of mice in the experimental groups was inhibited.Among them,P.polyphylla group,S.baicalensis group,compatibility 1∶2 group,compatibility 1∶1 group,and compatibility 2∶1 group had significant effects(P<0.05),and the inhibition rate of writhing was 20.43%,28.32%,52.30%,32.79%,and 39.02%,respectively.The analgesic effect of the compatibility 1∶2 group was the most obvious.(ii)In the hot plate experiment,compared with the blank control group,the experimental groups had analgesic effect.Among them,P.polyphylla group,S.baicalensis group,compatibility 1∶2 group,compatibility 1∶1 group,and compatibility 2∶1 group had significant effects(P<0.05),and the increase rate of pain threshold was 29.17%,47.83%,61.54%,and 50.61%,and 53.83%,respectively.The analgesic effect of the compatibility 2∶1 group was the most significant.(iii)In the hemostatic experiment,there was a significant difference in hemostatic time between the compatibility 1∶2 group and the blank control group,P.polyphylla group,and S.baicalensis group(P<0.05).The hemostatic effect of the compatibility 1∶2 group was the best.[Conclusions]P.polyphylla,S.baicalensis,and its compatibility had good analgesic and hemostatic effects,and the best compatibility ratio was 1∶2.Shibo ZHAO Suoyi HUANG Zhenjing SI Lanlan GAN Shusheng HUANG Ye FU Jianjie LAN Xueying YU Yuekong CEN 2020Medicinal Plant2020,11,2:2
11Environmental changes and lake level fluctuation recorded by lakes on the plain in northern Xinjiang during the late Holocene显示文摘Xinjiang 自治区域位于干旱区域在那里的 Chinaand 西是关于过去的温度和潮湿的变化的许多争论。大多数在北 Xinjiang 的平原上的湖是封上的湖和终端湖。他们能显然在 palaeoclimate 反映变化。在 northernXinjiang 的一些平凡的湖的 palaeoenvironmental 变化将从西昌·莱克, DongdaohaiziLake 和艾比·莱克主要基于花粉,沉积外形,点火(LOI ) 上的损失,危险性和谷物尺寸的数据在迟了的 Holocene 期间被分析。结果揭示温度和 bycold 湿、温暖干燥的统治的潮湿的一个装配模式。另外,影响因素将被讨论。FENG Xiaohua YAN Shun NI Jian KONG Zhaochen YANG Zhenjing 2006Chinese Science Bulletin2006,51,A01:2
12THE CO-RELATIONSHIP BETWEEN NEIGUAN POINT AND THE HEART AND REGULATION OF AMYGDALOID NUCLEI显示文摘In this present study, the ruodel of the rabbit with acute myocardial ischemia(AMI) was used to explore mechanisms of interrelation hetween Neiguan acupoint (PC 6) of the Peri-cardium Meridian and the heart hy employing physiological and morphologicaI methods. It wasdemonstrated that electroacupuncture (EA) at Neiguan (PC 6 ) couId raise the eIectrical excitahility ofischemic myocardium, lessen the dispersity of recovery excitability, correct the disorder of electricalactivity; protect myocardiac glycogen and phosphorylase and alleviate their depletion, increase contentof ribonuclei acid (RNA ), etc., indicating that EA could help oxidative rnetaholism carry out normal-Iy and irnProve nutritional state of the ischemic myocardiurn. The key point of EA action is probablyregulates the coronary microclrculation of heart and reclistributes myocardial blood flow. Studies withalkaline phosphatase (ALP ), Mg2--ATPase and ABS casting of the Ieft coronary artery showed thatafter EA the number and the IengthCao Qingshu, Wen Shen, Liu Junling, Han Zhenjing, Chen ShupingInstitute of Acupuncture and Moxibustion , China Academy of TCM, Beijing 100700 , China 1995World Journal of Acupuncture-Moxibustion1995,5,2:1
13Differences between the metabolic profiles of decompensated and compensated cirrhosis patients with Hepatitis B virus infections under high-performance liquid chromatography-mass spectrometry显示文摘Yu Chen Zhiliang Xu Hongwei Kong Nan Chen Jing Chen Lina Zhou Feiling Wang Yuejiao Dong Shufa Zheng Zhenjing Chen Guowang Xu Lanjuan Li 2012Metabolomics2012,,5:1
14Sensors Network for Ultrasonic Ranging System显示文摘Tao Gao Zhenjing Yao 2013International Journal of Advanced Pervasive and Ubiquitous Computing (IJAPUC)2013,5,3:1
15Advance in the synthesis of aromatic amine via direct animation显示文摘Arylamines are very common and important organic molecules. Acting as important intermediates in medical and chemical industry, they are widely used in the synthesis of Pharmaceuticals, dyes, pesticides, rubber additives, isocyanates and heterocyclic compounds. The traditional methods for the synthesis of arylamines include several steps. The production of aniline, for example, includes the following steps: the production of nitro-benzene by the nitration of benzene, and the reduction of theTong Chen Changwei Hu Zhenjing Fu Anmin Tian 2002Chinese Science Bulletin2002,47,23:1
16Quantitative real-time PCR analysis of intestinal regular fungal species in fecal samples from patients with chronic hepatitis B virus infection显示文摘Renyong Guo Zhenjing Chen Nan Chen 2010Laboratory Medicine2010,41,10:1
17Expression profile of early responsive genes under salt stress in upland cotton (Gossypium hirsutum L)显示文摘Zhang X ZhenJ B Li Z H 2011Plant Mol Bioi Rep2011,29,:1
18MicroRNA expression in theembryonic mouse inner ear 显示文摘Wang X R Zhang X M ZhenJ 2010Neuroreport2010,21,9:1
19Bidirectional Immunomodulatory Activities of Polysaccharides Purified From Pleurotus nebrodensis显示文摘Changlu Wang Haiyan Cui Yurong Wang Zhifang Wang Zhenjing Li Mianhua Chen Fengjuan Li 2014Inflammation2014,,1:1
20Heat and mass transfer model optimization and annual energy efficiency analysis for energy recovery indirect evaporative cooling显示文摘Indirect evaporative cooling(IEC)is a kind of high efficiency,energy-saving and environmental protection cooling technology,which has been widely used in data centers and other fields in recent years.In this paper,the optimized two-dimensional non-condensation state model of indirect evaporative cooling was proposed.Meanwhile the computer program was updated to solve the developed mathematical model under variable fresh air conditions.The optimized model was verified by the experimental data,and the maximum deviation was only 4.6%.Based on the modified model and the annual hourly meteorological parameters in Tianjin,China,it was analyzed the optimal heat transfer area of IEC used as fresh air pre-cooling unit under various air volumes to provide references for system design and equipment selection.Finally,taking an IEC-primary return air conditioning system of a gymnasium as an example,the hourly energy-saving effect of whole year was simulated by the developed IEC model.The simulation results showed that IEC could control the fresh air temperature below 27℃ and the moisture content below 18 g/kg throughout the year,and undertook 102.6% of the total fresh air cooling load.The findings are useful in future system optimization and design of IEC equipment.Qilong Liu Chunmei Guo Zhenjing Wu Yuwen You Yan Li 2022Building Simulation2022,15,7:0
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