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| 1 | 地下水开采对河流流量衰减的影响分析——以美国内布拉斯加州普拉特河谷为例显示文摘以内布拉斯加州普拉特河谷为例,详细分析了地下水开采对河流流量衰减的影响。计算了从1981年10月1日~1986年9月30日5年期间,普拉特河南、北两侧在抽水期间和抽水后期河流基流的减少和河流入渗的增加。其结果表明:无论是南侧还是北侧,抽水后期对河流流量影响的程度要明显大于抽水期间的;在河流南、北侧,抽水对河流基流的减少和河流入渗的增加影响恰恰相反。抽水在河流南侧对河流基流量减少的影响要明显大于河流的北侧,对河流渗漏量增加的影响却明显小于河流的北侧。这是因为在河流南侧,地下水水位高出河水位的值要大于河流的北侧。地下水位高出河水位的值越大,抽水对河流基流量减少的影响越明显,对河流渗漏增加的影响却微弱。这些信息对该地区,或类似地区水资源的合理开发利用是极其重要的。 | 束龙仓 Xunhong Chen | 2003 | 水利学报2003，34，2： | 15 |
| 2 | 美国内布拉斯加州埃尔克霍恩河河床沉积物渗透系数深度变化特征显示文摘准确计算河床沉积物渗透系数对于河流-地下水相互关系及其流域生态系统分析具有十分重要的作用.采用水头下降竖管渗透试验法对美国内布拉斯加州埃尔克霍恩河(Elkhorn River)8个不同地点、共60个试验点位上的河床上、下两层沉积物垂向渗透系数(Kv)做了试验研究.结果表明:上层沉积物Kv值普遍高于下层沉积物的.从所有测试点来看,上层沉积物中Kv测试值在2.7~104.9m/d之间,其平均值为26.6m/d;而下层沉积物Kv测试值在0.4~73.4m/d之间,其平均值为16.1m/d.河床沉积物Kv值随深度增加而减小这一现象主要是由于河流-地下水交错带水文过程引起的.交错带中水流流出和流入的交换作用增加了河床孔隙度从而增加了沉积物渗透性.此外,生物扰动作用能够有效地破坏河床表面细小沉积物形成的淤塞层,在沉积物中产生新的孔隙空间,从而增大了河床表层沉积物渗透系数. | 宋进喜 CHEN XunHong CHENG Cheng WANG DeMing 王文科 | 2009 | 科学通报2009，54，24： | 14 |
| 3 | 中美地下水资源开发利用对比分析显示文摘中国和美国分别作为发展中国家和发达国家的代表,两国开发利用地下水较早,在地下水开发利用过程中积累了丰富的经验。通过介绍两国地下水资源开发利用的现状,揭示其多年地下水用水量的变化规律,并进行对比分析。结果表明:近年来,两国地下水用水量仍超过1000×10~8m^3/a,地下水用水量占总用水量的比例均为20%左右,其中约有60%用于农业灌溉,三个指标整体上均呈现减少趋势。在人口、人均GDP和有效灌溉面积三个影响因素中,两国地下水用水量的首要影响因素均是有效灌溉面积。调水工程的兴建,可缓解地下水开采压力,有效地减少了地下水用水量。与美国相比,中国的用水效率较低,今后应进一步推广节水技术,加强地下水资源管理。 | 李璇 束龙仓 CHEN Xunhong | 2016 | 水文地质工程地质2016，43，2： | 9 |
| 4 | Generation of the regulatory protein rtTA transgenic mice显示文摘AIM: To translate Tet-on system into a conditional mouse model, in which hepatitis B or C virus (HBV or HCV) gene could be spatiotemporally expressed to overcome 'immune tolerance' formed during the embryonic development and 'immune escape' against hepatitis virus antigen(s), an effector mouse, carrying the reverse tetracycline-responsive transcriptional activator (rtTA) gene under the tight control of liver-specific human apoE promoter, is required to be generated. METHODS: To address this end, rtTA fragment amplified by PCR was effectively inserted into the vector of pLiv.7 containing apoE promoter to create the rtTA expressing vector, I.e., pApoE-rtTA. ApoE-rtTA transgenic fragment (-6.9 kb) released from pApoE-rtTA was transferred into mice by pronucleus injection, followed by obtaining one transgene (+) founder animal from microinjection through PCR and Southern blot analysis.RESULTS: rtTA transgene which could be transmitted to subsequent generation (F1) derived from founder was expressed in a liver-specific fashion. CONCLUSION: Taken together, these findings demonstrate that rtTA transgenic mice, in which rtTA expression is appropriately targeted to the murine liver, are successfully produced, which lays a solid foundation to 'off-on-off' regulate expression of target gene (s) (e.g., HBV and/or HCV) in transgenic mice mediated by Tet-on system. | KangXu Xin-YanDeng YingYue Zhong-MinGuo BingHuang XunHong DongXiao Xi-GuChen | 2005 | World Journal of Gastroenterology2005，11，19： | 7 |
| 5 | Groundwater evapotranspiration under psammophilous vegetation covers in the Mu Us Sandy Land, northern China显示文摘Groundwater is a significant component of the hydrological cycle in arid and semi-arid areas. Its evapotranspiration is an important part of the water budget because many plants are groundwater-dependent. To restore the degraded ecosystems, the need is pressing to further our understanding of the groundwater evapotranspiration(ET_g) in arid and semi-arid areas. This study employed the White method to estimate ET_g at four sites in the Mu Us Sandy Land in northern China, and the four sites are covered by Salix psammophila(SP site), Artemisia ordosica(AO site), Poplar alba(PA site), and Carex enervis(CE site), respectively. The depth of groundwater table and the duration of drainage were taken into account in calculating the specific yield(S_y) to improve the accuracy of the ET_g estimats. Our results showed that from late May to early November 2013 the ET_g were 361.87(SP site), 372.53(AO site), 597.86(PA site) and 700.76 mm(CE site), respectively. The estimated ET_g rate was also species-dependent and the descending order of the ET_g rate for the four vegetation was: C. enervis, P. alba, A. ordosica, and S. psammophila. In addition, the depth of groundwater table has an obvious effect on the ET_g rate and the effect varied with the vegetation types. Furthermore, the evapotranspiration for the vegetation solely relying on the water supply from unsaturated layers above the groundwater table was much less than that for the vegetation heavily relying on the water supply from shallow aquifers. | CHENG Donghui DUAN Jibo QIAN Kang QI Lijun Yang Hongbin CHEN Xunhong | 2017 | Journal of Arid Land2017，9，1： | 4 |
| 6 | Temporal Control of Cre Recombinase-mediated in Vitro DNA Recombination by Tet-on Gene Expression System显示文摘Conditional gene expression and gene deletion are important experimental approaches for examining the functions of particular gene products in mouse models. These strategies exploiting Cre-mediated site-specific DNA recombination have been incorporated into transgenic and gene-targeting procedures to allow in vivo manipulation of DNA in embryonic stem cells (ES cells) or living animals. The Cre/lox P system has become widely used in conditional gene targeting, conditional gene repair and activation, inducible chromosome translocation, and chromosome engineering. In this project, we have employed the universal transgenic system and the liver-specific promoter system for tightly temporal and liver-specific control of Cre gene expression in mice that (1) integrates the advantages of the Tet-on gene expression system and Cre/lox P site-mediated gene activation, and (2) simplifies the scheme of animal crosses through a combination of two control elements in a single transgene. A liver-specific apoE promoter was inserted into the promoter cloning site upstream of the rtTA cassette of pCore construct to generate the transgene construct pApoErtTA-tetO-Cre, followed by demonstrating stringent regulation of doxycycline (Dox)-induced Cre-mediated recombination in the lox P-flanked transcription STOP cassette-modified BEL-7402 cells. That is to say, in the absence of Dox, the Cre gene is not expressed and will not induce site-specific recombination between two lox P sites, whereas on exposure to Dox, the Cre gene will be expressed and the recombination will occur.Together, these data indicate that the Tet-on gene expression system is able to successfully and stringently control Cre expression in vitro, which lays a solid foundation for efficient and spatio-temporal Cre gene activation in transgenic mice. | Zhong-MinGUO KangXU YingYUE BingHUANG Xin-YanDENG Nü-QiZHONG XunHONG Xi-GuCHEN DongXIAO | 2005 | Acta Biochimica et Biophysica Sinica2005，37，2： | 3 |
| 7 | Simultaneous chromatographic fingerprinting and quantitative analysis of flavonoids in Pollen Typhae by high-performance capillary electrophoresis显示文摘To evaluate the quality of Pollen Typhae as used in traditional Chinese medicine,a high-performance capillary electrophoresis(HPCE)method has been developed,validated and applied to chromatographic fingerprinting and quantitation of its eight main bioactive flavonoids(naringenin,isorhamnetin 3-0-(2^(G)-α-L-rhamnosy)-rutinoside,rhamnetin 3-0-neohesperidoside,isorhamnetin,quercetin 3-0-(2^(G)-α-L-rhamnosyl)-rutinoside,quercetin 3-O-neohesperidoside,kaempferol and quer-cetin).Fingerprinting was based on the selection of nine characteristic chromatographic peaks.In quantitative analysis,the recovery of all eight compounds was in the range 98.5-102.2% with good linearity(r^(2)>0.9919)over a relatively wide concentration range.The assay was successfully applied to the analysis of the eight bioactive flavonoids in 14 different samples.The results indicate that the assay is reproducible and precise and can be used for convenient quality assessment of Pollen Typhae. | Le Han Xunhong Liu Nianyun Yang Junsong Li Baochang Cai Shi Cheng | 2012 | Acta Pharmaceutica Sinica B2012，2，6： | 3 |
| 8 | 西安市曲江南湖富营养化遥感监测与评价显示文摘目前中国城区景观水体氮、磷营养盐含量高,藻类泛滥,水生生态系统较为单一,大多呈现富营养化状态。以西安市辖区内的曲江南湖景观水体为研究区,将地面实测资料和Landsat5 TM各波段的卫星遥感数据反演结果进行对比,通过相关分析,建立了4个水质参数浓度与TM波段比TM4/TM3之间的线性关系模型,并采用综合营养状态指数法对城市景观水体富营养化进行了综合评价。结果表明:利用叶绿素a遥感估测模型对景观水体富营养化状况进行监测,能够获取较为准确的监测结果;综合营养状态指数法可以对曲江南湖景观水体富营养化程度进行正确评价,评价结果显示曲江南湖呈现轻度到中度富营养化状态,需要采取有力的保护措施防止水质进一步恶化。 | 何红曼 米海存 霍艾迪 Xunhong Chen | 2013 | 中国水土保持2013，，9： | 3 |
| 9 | Variability of streambed vertical hydraulic conductivity with depth along the Elkhorn River,Nebraska,USA显示文摘Determination of streambed hydraulic conductivity is of great importance in the analysis of stream-aquifer interactions and stream ecosystems.In this paper,in situ falling-head standpipe permeameter tests were conducted to determine streambed vertical hydraulic conductivity (Kv) of two connected layers of sediments at 60 test locations from eight sites in the Elkhorn River,Nebraska.Our results show that the Kv values for the upper layer of sediments are generally larger than those in their respective lower layer of sediments.The individual Kv value for the upper layer of sediments from all test locations of the eight sites range from 2.7 to 104.9 m/d,and the average value is 26.6 m/d.The individual Kv value ranges from 0.4 to 73.4 m/d and the average value is 16.1 m/d for the lower layer of sediments.We believe that hyporheic processes can enhance larger streambed Kv in the upper layer of sediments.Inflow and outflow through hyporheic zone produce more porous and permeable sediments and further result in an increasing of streambed Kv.Moreover,we observe that bioturbation activities can destroy the clogging layer of the exposed sediments and create pore spaces in the sediments,which also further increases streambed Kv. | SONG JinXi CHEN XunHong CHENG Cheng WANG DeMing WANG WenKe | 2010 | Chinese Science Bulletin2010，55，10： | 2 |
| 10 | Observation of bioturbation and hyporheic flux in streambeds显示文摘In the Elkhorn River,burrows,tubes,and sediment mounds created by invertebrate bioturbation were observed in the exposed streambed and commonly concentrated on the fine-sediment patches,which consist of silt,clay,and organic matter.These invertebrate activities could loosen the thin layer of clogging sediments and result in an increase of pore size in the sediments,leading to greater vertical hydraulic conductivity of the streambed(Kv).The measurements of the vertical hydraulic gradient across the submerged streambed show that vertical flux in the hyporheic zone can alter directions(upward versus downward)for two locations only a few meters apart.In situ permeameter tests show that streambed Kv in the upper sediment layer is much higher than that in the lower sediment layer,and the calculated Kv in the submerged streambed is consistently greater than that in the clogged sediments around the shorelines of the sand bars.Moreover,a phenomenon of gas bubble release at the water-sediment interface from the subsurface sediments was observed in the groundwater seepage zone where flow velocity is extremely small.The bursting of gas bubbles can potentially break the thin clogging layer of sediments and enhance the vertical hydraulic conductivity of the streambed. | Jinxi SONG Xunhong CHEN Cheng CHENG | 2010 | Frontiers of Environmental Science & Engineering2010，4，3： | 2 |
| 11 | Survey on nonlinear reconfigurable flight control显示文摘An overview on nonlinear reconfigurable flight control approaches that have been demonstrated in flight-test or highfidelity simulation is presented.Various approaches for reconfigurable flight control systems are considered,including nonlinear dynamic inversion,parameter identification and neural network technologies,backstepping and model predictive control approaches.The recent research work,flight tests,and potential strength and weakness of each approach are discussed objectively in order to give readers and researchers some reference.Finally,possible future directions and open problems in this area are addressed. | Xunhong Lv Bin Jiang Ruiyun Qi Jing Zhao | 2013 | Journal of Systems Engineering and Electronics2013，24，6： | 2 |
| 12 | Friction stir welding of AZ31 magnesium alloys processed by equal channel angular pressing显示文摘Equal channel angular pressing (ECAP) is an effective thermo-mechanical process to make ultrafine grains. An investigation was carried out on the friction stir welding (FSW) of ECAPed AZ31 magnesium alloys with a thickness of 15 mm. For different process parameters, the op-timum FSW conditions of ECAPed AZ31 magnesium alloys were examined. The basic characterization of weld formation and the mechani-cal properties of the joints were discussed. The results show that the effect of welding parameters on welding quality was evident and weld-ing quality was sensitive to welding speed. Sound joints could be obtained when the welding speed was 37.5 mm/min and the rotation speed of the stir tool was 750 r/min. The maximum tensile strength (270 MPa) of FSW was 91% that of the base materials. The value of micro-hardness varied between advancing side and retreating side because of the speed field near the pin of the stir tool, which weakened the de-formed stress field. The value of microhardness of the welding zone was lower than that of the base materials. The maximum value was lo-cated near the heat-affected zone (HAZ). Remarkable ductile character was observed from the fracture morphologies of welded joints. | ZHANG Bing YUAN Shouqian WANG Xunhong | 2008 | Rare Metals2008，27，4： | 2 |
| 13 | Powerspectrum-analysis-based signal processing system of vortex flowmeters显示文摘 | Xu Kejun Huang Yunzhi Lii Xunhong | 2006 | IEEE Transactions on Instrumentation and Measurement2006，55，： | 1 |
| 14 | The Hydrologic Function and Behavior of the Houzhai Underground River Basin, Guizhou Prov- ince,Southwester China显示文摘 | Liu Lihong Shu Longcang Chen Xunhong | 2010 | Hydrogeology Journal2010，18，2： | 1 |
| 15 | Stream Water Infiltration,Bank Storage,and Storage Zone Changes due to Streamstage fluctuations显示文摘 | Chen Xi Xunhong Chen | 2003 | Journal of Hydrology2003，，280： | 1 |
| 16 | A new method for mapping variability in vertical seepage flux in streambeds显示文摘 | Xunhong Chen Jinxi Song Cheng Cheng Deming Wang Susan O. Lackey | 2009 | Hydrogeology Journal2009，，3： | 1 |
| 17 | Estimation of groundwater evaportranspiration using diurnal water table fluctuations in the Mu Us Desert, northern China显示文摘 | Dong-hui Cheng Ying Li Xunhong Chen Wen-ke Wang Guang-cai Hou Cun-liang Wang | 2013 | Journal of Hydrology2013，，： | 1 |
| 18 | As- sessment of Sustainable Yield of Karst Water in Huaibei, China显示文摘 | Yin Dan Shu Longcang Chen Xunhong | 2011 | Water Resources Management2011，，： | 1 |
| 19 | Measurement of streambed hydraulic conductivity and its anisotropy显示文摘 | Xunhong Chen | 2000 | Environmental Geology2000，，12： | 1 |
| 20 | Adaptive notch filter-based signal processing method and system for vortex flowmeter 显示文摘 | Xu Kejun Wang Anmin Lu Xunhong | 2001 | Review of Scientific Instruments2001，72，4： | 1 |
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