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Seasonal variations in the influence of vegetation cover on soil water on the loess hillslope

Journal of Mountain Science 2020年第9期17卷 2148-2160页

作者： SHEN Ming-shuang zhang Jian-jun zhang Shou-hong zhang Hai-bo SUN Ruo-xiu zhang yi-zhou School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China National Station for Forest Ecosystem Research in Ji County Ji County 042200Shanxi ProvinceChina

Soil water is the key factor that restricts the restoration of the local ecological systems in the Loess Plateau of *** the effects of vegetation types on soil water and its seasonal variation helps to understand hydrological characteristics and provides insights into the sustainable restoration of ***,the Caijiachuan watershed was chosen as the research object to investigate the water status of a 0-10 m soil layer under different vegetation types including Pinus tabulaeformis,Robinia pseudoacacia,Platycladus orientalis,apple orchard,natural forestland,farmland and *** comparing the difference between soil water of different land use types and that of grassland during the same period,the seasonal changes of soil water status of different types were *** results show that(1)in the 0-10 m soil layer,the largest value of soil water content was in the0.3-0.4 m layer,and the lowest was in the 5.6-5.8 m *** depths at which the vegetation cover influenced the soil water were up to 10 m;(2)among summer,fall and spring,the soil water storage wasthe highest in the *** addition,the lowest value of relative accumulation was in the fall,which was the period in which the soil water recovered;(3)the soil water in the 0-10 m layer was in a relatively deficient state in the artificial forestlands,apple orchards and native forestlands,while the relative accumulation was in the *** addition,the relative deep soil layers(8-10 m)had more serious deficits in the areas in which ***,*** and the apple orchard grew;(4)during the study period,the farmland in the summer had the largest relative accumulation(182.71 mm),and the land under *** in the fall had the lowest relative deficit(512.20 mm).In the Loess Plateau,vegetation cover will affect the change of deep soil moisture and artificial forest will cause soil water loss in different degrees.

关键词： Seasonal variation Soil water Vegetation cover Hillslope Loess Plateau

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Study on real working performance and overload safety factor of high arch dam

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Science China(Technological Sciences) 2008年第S2期51卷 48-59页

作者： zhang GuoXin,LIU yi & zhou QiuJing Department of Structures and Materials,China Institute of Water Resources and Hydropower Research,Beijing 100038,China Department of Structures and Materials China Institute of Water Resources and Hydropower Research Beijing China

Considering the fact that high arch dams have problems such as complicated stress,high cost,and hazards after being damaged,this paper intends to study the effects of load,material strength,and safety analysis method on dam safety and working performance of arch *** this article,the effects of temperature,self weight exaction way and water loading on structure response are first discussed,and a more reasonable way of considering is then put *** taking into consideration the mechanical property of materials and comparing the effects of different yield criteria on overloading safety of high arch dams,this paper concludes that brittle characteristics of concrete should be fully considered when conducting safety assessment for high arch dams to avoid overestimating the bearing capacity of the *** comparing several typical projects,this paper works out a safety assessment system of multiple safety and relevant engineering analogical analysis methods,which is closer to the actual situation,and thus is able to assess the response of high arch dam structure in a more comprehensive way,elicit the safety coefficients in different situations,and provide a new way of considering the safety assessment of high arch dams.

关键词： high arch dam real working performance safety load strength safety assessment method

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Contamination and browning in tissue culture of Platanus occidentalis L.

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Forestry Studies in China 2007年第4期9卷 279-282页

作者： Tao Feng-jie zhang Zhi-yi zhou Jun Yao Na Wang Dong-mei Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants Ministry of Education Beijing Forestry University100083 R R. China

Twigs of 2-3-year-old Platanus occidentalis L. were used as experimental material to find the causes for the contamination and browning in the initial stages of tissue cultures. To compare the degree of browning of explants picked off from different growing seasons, the experimental material was excised from trees on each of the first ten days in January, March, May and July, 2006. The results indicated that the contamination and browning rates of the material cut off in January （14.2% and 30.6%, respectively） and March were somewhat lower than those in July. The pretreatment of soaking the explants in different anti-oxidants and absorbents at the same time could diminish some side effects. The pretreatment of using 10 g·L^-1 vitamin C reduced the contamination and brown- ing rate effectively. An orthogonal experiment showed that the optimal factor and level arrangement is 0.5 mg·L^-1BA, 2.0 g·L^-1 active carbon and 1.5 g·L^-1 PVP which resulted in a browning rate of only 16.5%. In general, sampling period, physical properties and pretreatment of explants are the main factors responsible for the contamination and browning of material in the initial stages of P. occidentalis tissue cultures.

关键词： platanus occidentalis L. tissue culture contamination browning

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Intestinal stromal tumor coexisted with acute promyelocytic leukemia： a case report

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Chinese Medical Journal 2008年第18期121卷 1852-1853页

作者： LI Deng-ju zhang yi-cheng zhou Jian-feng TANG Jin-zhi Department of Hematology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Lower gastrointestinal hemorrhage is a nonspecific common symptom of both acute promyelocytic leukemia （APL） and gastrointestinal stromal tumors （GIST）. The possibility of GISTs is rarely considered in patients with APL when intestinal hemorrhage occurres. We treated a case of GISTs coexisting with APL in July 2006. The diagnosis of GIST was verified through surgery and pathological examination of the resected intestinal mass.

关键词： leukemia promyelocytic gastrointestinal stromal tumors gastrointestinal hemorrhage

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Function of Aurora kinase A in Taxol--resistant breast cancer and its correlation with P--gp

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中国药理通讯 2011年第2期28卷 33-34页

作者： Yan Li Ke Tang Haijing zhang yi zhang Wanqi zhou Xiaoguang Chen Department of Pharmacology Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050

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基于HPLC波长切换联合梯度洗脱技术的双参龙胶囊中10种主要成分定量研究

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中草药 2018年第5期49卷 1081-1086页

作者：张毅周慧天津市环湖医院天津市脑血管与神经变性重点实验室天津300350 天津医科大学药学院实验中心天津300070

目的建立HPLC波长切换联合梯度洗脱法(HPLC-DVD法)同时测定双参龙胶囊(SSLC)中毛蕊异黄酮葡萄糖苷、鲁斯可皂苷元、苦杏仁苷、人参皂苷Rb_1、人参皂苷Re、阿魏酸、西红花苷-I、丹酚酸B、11-羰基-β-乙酰乳香酸和丹参酮Ⅱ_A 10种指标成... 详细信息

目的建立HPLC波长切换联合梯度洗脱法(HPLC-DVD法)同时测定双参龙胶囊(SSLC)中毛蕊异黄酮葡萄糖苷、鲁斯可皂苷元、苦杏仁苷、人参皂苷Rb_1、人参皂苷Re、阿魏酸、西红花苷-I、丹酚酸B、11-羰基-β-乙酰乳香酸和丹参酮Ⅱ_A 10种指标成分的方法。方法采用HPLC-DVD法,Hypersil ODS C_(18)(150 mm×4.0 mm,3μm)色谱柱;甲醇-水(8∶2,A)-0.1%磷酸水溶液(B)为流动相,梯度洗脱,体积流量0.6 mL/min;毛蕊异黄酮葡萄糖苷的检测波长为260 nm,鲁斯可皂苷元的检测波长为280 nm,苦杏仁苷的检测波长为210 nm,人参皂苷Rb_1和人参皂苷Re的检测波长为203 nm,阿魏酸的检测波长为320 nm,西红花苷I的检测波长为440 nm,丹酚酸B的检测波长为286 nm,11-羰基-β-乙酰乳香酸的检测波长为250 nm,丹参酮Ⅱ_A的检测波长为270 nm;进样量为10μL。结果 10种指标成分毛蕊异黄酮葡萄糖苷在3.88~69.86mg/L(r=0.999 2)、鲁斯可皂苷元在22.1~397.8 mg/L(r=0.999 1)、苦杏仁苷在37.43~673.5 mg/L(r=0.999 4)、人参皂苷Rb_1在45.15~812.72 mg/L(r=0.999 6)、人参皂苷Re在4.55~81.95 mg/L(r=0.999 5)、阿魏酸在3.06~55.15 mg/L(r=0.999 4)、西红花苷-I在1.93~34.76 mg/L(r=0.999 5)、丹酚酸B在15.68~282.15 mg/L(r=0.999 6)、11-羰基-β-乙酰乳香酸在11.31~203.58 mg/L(r=0.999 1)、丹参酮Ⅱ_A在1.89~34.16 mg/L(r=0.999 6)质量浓度与峰面积具有较好的线性关系;精密度良好,RSD≤1.27%;重复性良好,RSD≤1.28%;供试品溶液在室温条件下8 h内稳定,RSD≤0.96%;平均加样回收率和相应的RSD分别为99.61%、1.21%,100.11%、0.76%,101.52%、0.62%,101.22%、1.03%,100.83%、1.14%,98.94%、0.53%,101.04%、1.09%,100.05%、1.25%,99.81%、0.68%,101.94%、1.31%。9批次供试品中毛蕊异黄酮葡萄糖苷、鲁斯可皂苷元、苦杏仁苷、人参皂苷Rb_1、人参皂苷Re、阿魏酸、西红花苷-I、丹酚酸B、11-羰基-β-乙酰乳香酸和丹参酮Ⅱ_A量分别为0.142~0.158、0.747~0.764、1.578~1.619、2.163~2.185、0.235~0.251、0.557~0.580、0.105~0.122、0.311~0.328、0.605~0.624、0.062~0.079 mg/粒。结论建立的HPLC-DVD法同时测定SSLC中的10种成分,方法操作简便、快速、准确,可作为SSLC质量控制的分析方法。

关键词： HPLC-DVD法双参龙胶囊毛蕊异黄酮葡萄糖苷鲁斯可皂苷元苦杏仁苷人参皂苷Rb1 人参皂苷Re 阿魏酸西红花苷-I 丹酚酸B 11-羰基-β-乙酰乳香酸丹参酮Ⅱ_A

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一种船舶自动识别系统甚高频信道的低成本设计

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电讯技术 2014年第4期54卷 480-485页

作者：张翼周成都天奥信息科技有限公司成都611731

随着船舶自动识别系统(AIS)市场竞争的日益激烈,低成本化是AIS产品研制的必然趋势。根据国际海事组织(IMO)有关标准,给出了一种AIS甚高频(VHF)信道的低成本设计方案。介绍了AIS工作原理及其VHF信道的工作过程,给出了简洁实用的发射机和... 详细信息

随着船舶自动识别系统(AIS)市场竞争的日益激烈,低成本化是AIS产品研制的必然趋势。根据国际海事组织(IMO)有关标准,给出了一种AIS甚高频(VHF)信道的低成本设计方案。介绍了AIS工作原理及其VHF信道的工作过程,给出了简洁实用的发射机和接收机设计,并对调制器、VHF功放、解调器等核心单元设计方法、器件选择进行了详细阐述。测试和外场实用表明该VHF信道各项指标均已达到规定要求,并且该VHF信道硬件成本低,性能可靠。

关键词：船舶自动识别系统 VHF信道 VHF功放调频解调高斯滤波最小移频键控低成本设计

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新体制民用航海雷达的应用与发展

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电讯技术 2014年第6期54卷 857-862页

作者：张翼周成都天奥信息科技有限公司成都611731

传统磁控管雷达已占据民用航海雷达领域较长的一段时间,新技术新体制在这一领域的应用给民用航海雷达发展带来了新的机遇。以近年出现的新型民用航海雷达为背景,简述了民用航海雷达的分类、原理组成和发展现状,介绍了航海雷达使用的新... 详细信息

传统磁控管雷达已占据民用航海雷达领域较长的一段时间,新技术新体制在这一领域的应用给民用航海雷达发展带来了新的机遇。以近年出现的新型民用航海雷达为背景,简述了民用航海雷达的分类、原理组成和发展现状,介绍了航海雷达使用的新技术以及在溢油探测、海浪监测领域的新应用,指出固态发射、数字化、综合导航、低辐射将是民用航海雷达的发展方向,这些新技术的使用将提高航海雷达的可靠性和环境适应性。

关键词：航海雷达固态功放脉冲压缩海杂波抑制

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《仪礼·士昏礼》妇馈舅姑考辨

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华侨大学学报（哲学社会科学版） 2022年第3期 121-129,142页

作者：张逸舟福建师范大学文学院/经学研究所福建福州350007

《仪礼·士昏礼》妇馈舅姑仪节中的若干问题,前人争论不休。或不明舅姑共席,比如黄以周《礼书通故》;或不明舅姑异俎,比如盛世佐《仪礼集编》;或不明“易酱”当更换舅之馔肴,比如敖继公《仪礼集说》;或不明“始饭之错”深意,比如俞樾《... 详细信息

《仪礼·士昏礼》妇馈舅姑仪节中的若干问题,前人争论不休。或不明舅姑共席,比如黄以周《礼书通故》;或不明舅姑异俎,比如盛世佐《仪礼集编》;或不明“易酱”当更换舅之馔肴,比如敖继公《仪礼集说》;或不明“始饭之错”深意,比如俞樾《群经平议》。今以《仪礼·士昏礼》经注疏为依据,疏通考核历代学者观点,详加折衷,可得礼意。

关键词：《仪礼·士昏礼》妇馈舅姑馂余

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Low-lossfiber optic rotaryjoint using C-lens colli mators

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Optoelectronics Letters 2005年第3期1卷 221-223页

作者： JIA Da-gong JING Wen-cai zhang yi-mo zhou Ge zhang Jin TANG Feng College of Precision Instrument ＆ Opto-electronics Engineering Key Loboratory of Opto-electronics Information and Technical Science Ministry of Education Tianjin University Tianjing 300072 China

A low-loss fiber optic rotary joint (FORJ) has been designed by using two kinds of C-lens collimators. Its insertion loss and insertion loss variation due to rotation with single-mode fiber collimator is less than 1.76 dB and 0.43 dB *** maximum insertion loss and coupling variation due to rotation with multi-mode fiber collimator is 1.71 dB and 0.29 dB, respectively. This kind of FORJ features low insertion loss, small coupling variation due to rotation and low cost.

关键词：光纤 C透镜瞄准仪光学旋转

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