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Causes of maize density loss in farmers’ fields in Northeast China

Journal of Integrative Agriculture 2019年第8期18卷 1680-1689页

作者： ZHAO Ying-jie XING Sen zhang qing-song zhang Fu-suo MA Wen-qi Key Laboratory of Plant-Soil Interactions Ministry of Education Beijing 100193 P.R.China College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R.China College of Resources and Environmental Science Hebei Agricultural University Baoding 071001 P.R.China

Increasing plant density is an effective and important way to reduce maize yield gaps in Northeast China. However, the fact is that a significant plant density gap exists between optimum plant density and actual plant density in farmers’ *** quantify the density gap between planned planting density and final harvest plant density(HPD), we studied 60 farmers’ fields on three types of soil for three crop seasons from 2015 to 2017 by measuring their plant-plant distance, actual seedlings density(ASD), final HPD and yield. We also explored the potential causes of density loss by digging the places where the seedlings were missing for two consecutive years in 2016–2017. Results show that the three-year average HPD in farmers’ fields was 59 699 plants ha^–1, which was significantly lower than the planned density, including both the machine setting density(MSD;67 962 plants ha^–1) and theoretical plant density(TPD;67 467 plants ha^–1). No significant difference was found in HPD between years and soil types. However, for MSD and TPD, the average value in 2015 was significantly higher than that in 2016 and 2017. No significant difference between soil types was observed. Furthermore,the results from 2016 till 2017 indicated that a lack of seeds in the soil, a failure to germinate due to low-quality seeds,and a lack of seedlings breaking out of the soil due to environmental problems explained approximately 60.88, 10.33 and 28.80% of density loss, respectively. According to our survey, 63% of farmers did not know their own TPD and HPD, and 54% of farmers did not know the density loss. Therefore, we argue that farmers’ limited knowledge of density and density loss is an urgent problem that needs to be solved in maize production. These observations will be useful for determining best management practices for maize production and for providing helpful suggestions for machine improvement.

关键词： plant density maize production density loss density gap farmers’ fields

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Cohesion variation during instability evolution of disaster medium in mud inrush of mountain tunnel

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Journal of Mountain Science 2019年第11期16卷 2519-2531页

作者： YANG Teng zhang qing-song zhang Xiao LI Xiang-hui zhang Jia-qi SUN Yu-xue LI Zhuang Geotechnical & Structural Engineering Research Center Shandong University

Mud inrush in mountain tunnel is an independent geological hazard type different from water inrush,landslide and debris *** intrinsic factor of mud inrush is the instability failure of disaster *** essence is that when the cohesion decreases gradually with the increase of void ratio to the point where the movement of soil particles cannot be restricted,soil particles and groundwater form slurry and gush ***,accurate calculation of cohesion with variable void ratios is crucial for analyzing the reliability of disaster *** this study,the disaster medium was regarded as graded soil and a structural model was established wherein soil particles were simplified as cubes and the inter-particle pores were represented by the clearance between *** the basis of the structure model of disaster medium,a function between the soil particle distance and void ratio was *** is equivalent to the resultant force between soil particles per unit area;thus,a cohesion function was derived in which the void ratio is the main *** function considers the influence of gradation characteristics on cohesion variation and is generally applicable to various types of disaster medium.A series of direct shear tests were carried out to determine the cohesion variation for different types of disaster medium with variable void *** comparing the variation of cohesion obtained through direct shear tests with those deduced by the proposed cohesion function,we verified the validity and general applicability of the cohesion *** is of great significance because the cohesion function can accurately predict the variation of cohesion by using the void ratio,and effectively evaluate the possibility of mud inrush according to the initial mechanical properties of disaster medium.

关键词： Cohesion Disaster medium Graded soil Structure model Void ratio Shear test

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Detection and treatment of water inflow in karst tunnel：A case study in Daba tunnel

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Journal of Mountain Science 2018年第7期15卷 1585-1596页

作者： LI Xiang-hui zhang qing-song zhang Xiao LAN Xiong-dong DUAN Chong-hao LIU Jian-guo geotechnical & Structural Engineering Research Center Shandong UniversityJinan 250061 China

In a karst tunnel, fissures or cracks that are filled with weathered materials are a type of potential water outlet as they are easily triggered and converted into groundwater outlets under the influence of high groundwater pressure. A terrible water inrush caused by potential water outlets can seriously hinder the project construction. Potential water outlets and water sources that surrounding the tunnel must be detected before water inflow can be treated. This paper provides a successful case of the detection and treatment of water inflow in a karst tunnel and proposes a potential water outlet detection(PWOD) method in which heavy rainfall(>50 mm/d) is considered a trigger for a potential water outlet. The Daba tunnel located in Hunan province, China, has been constructed in a karst stratum where the rock mass has been weathered intensely by the influence of two faults. Heavy rain triggered some potential water outlets, causing a serious water inrush. The PWOD method was applied in this project for the treatment of water inflow, and six potential water outlets in total were identified through three heavy rains. Meanwhile, a geophysical prospecting technique was also used to detect water sources. The connections between water outlets and water sources were identified with a 3-D graphic that included all of them. According to the distribution of water outlets and water sources, the detection area was divided into three sections and separately treated by curtain grouting.

关键词： Karst tunnel Water inrush Potential water outlet detection Geophysical prospecting technique Water inflow Grouting

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Study on the composite Nd:YAG crystal by laser micro-Raman spectroscopy

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Optoelectronics Letters 2007年第6期3卷 441-443页

作者： SUN Dun-lu zhang qing-li WAN song-ming JIANG Hai-he YIN Shao-tang Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences HeFei 230031 China

The composite Nd：YAG crystal with undoped YAG end caps was fabricated by thermal bonding technique. Scanning electron microscopy （SEM） result shows that the width of the bonded interface was about 0.5 lain. The laser micro-Raman was used to study the bonded interface of the composite crystal. The results of Raman spectra and the bonded interface image indicate that the undoped YAG and Nd：YAG crystals have been well bonded together. Furthermore, it can be drawn that the structure and the composition of the bonded interface are the same as the undoped YAG crystal, and that the Nd^3＋ ions do not enter the bonded interface and the YAG side. This property is advantageous to decrease the thermal effect of the boned interface and to improve the laser stability.

关键词：晶体生长 Nd:YAG 物理性质光谱激光

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Pharmacokinetics and biodistribution of polymeric micelles of paclitaxel with Pluronic P123

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Acta Pharmacologica Sinica 2006年第6期27卷 747-753页

作者： Li-mei HAN Jie GUO Li-jun zhang qing-song WANG Xiao-ling FANG~2 Department of Pharmaceutics.School of Pharmacy,Fudan University,Shanghai 200032,China Department of Pharmaceutics School of Pharmacy Fudan University Shanghai China

Aim:To investigate the preparation,in vitro release,in vivo pharmacokineticsand tissue distribution of a novel polymeric micellar formulation of paclitaxel(PTX)with Pluronic ***:The polymeric micelles of paclitaxel with PluronicP123 were prepared by a solid dispersion *** characteristics of micellesincluding particle size distribution,morphology and in vitro release of PTX frommicelles were carried ***-loaded micellar solutions were administered throughthe tail vein to healthy Sprague-Dawley rats and Kunming strain mice to assessthe pharmacokinetics and tissue distribution of PTX,***,thecommercially available intravenous formulation of PTX,was also administered ***:By using a dynamic light scattering sizer and a transmissionelectron microscopy,it was shown that the PTX-loaded micelles had a mean sizeof approximately 25 nm with narrow size distribution and a spherical *** continuously released from Pluronic P 123 micelles in release medium contain-ing 1 mol/L sodium salicylate for 24 h at 37℃.In the pharmacokinetic assessment,t1/2βand AUC of micelle formulation were 2.3 and 2.9-fold higher than that of *** the PTX-loaded micelles increased the uptake of PTX in the plasma,ovary and uterus,lung,and kidney,but decreased uptake in the liver and brain inthe biodistribution ***:Polymeric micelles using Pluronic P123can effectively solubilize PTX,prolong blood circulation time and modify thebiodistribution of PTX.

关键词： paclitaxel micelle Pluronic P123 pharmacokinetics biodistribution

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Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang JIANG Tian MAO Jin-song WANG Xiu-qing HU Xiao-Xin zhang Liping FU Nan JIA Tianfang WANG National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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对全流量补燃循环发动机系统的研究与分析

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航空动力学报 2005年第2期20卷 328-333页

作者：胡伟张青松北京航空航天大学宇航学院北京100083

论述了全流量补燃循环氢氧发动机的工作过程,并给出了基于这种循环方式的发动机的系统简图。根据现有的氢氧发动机的研制现状,针对全流量补燃发动机进行了系统参数的平衡计算。从这种循环方式的工作机理出发,结合参数计算得到的结果对... 详细信息

论述了全流量补燃循环氢氧发动机的工作过程,并给出了基于这种循环方式的发动机的系统简图。根据现有的氢氧发动机的研制现状,针对全流量补燃发动机进行了系统参数的平衡计算。从这种循环方式的工作机理出发,结合参数计算得到的结果对这种循环方式的发动机的先进性进行了讨论。认为这种循环方式的氢氧发动机可以具有更高的可靠性,以及能够获得更高的性能,能够满足人们现在对高可靠性,低成本,可重复使用的液体火箭发动机的要求。

关键词：航空、航天推进系统全流量补燃循环预燃室涡轮泵液体火箭发动机

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高自旋场对Vaidya-Bonner黑洞熵的贡献

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物理学报 2005年第11期54卷 5500-5503页

作者：张建华张青松山东省菏泽学院物理系菏泽274015 东华大学材料学院上海200051

利用改进的brick-wall模型推导出自旋为2的引力场对动态Vaidya-Bonner黑洞熵的贡献,在自然单位制中其值为A/2;这表明,当选择与标量场相同的截断因子时,其熵为标量场的2倍,为Dirac场的4/7.

关键词： Vaidya-Bonner黑洞,黑洞熵,高自旋场,薄膜brick-wall模型黑洞熵自旋场 Dirac场自然单位制模型推导截断因子标量场引力场

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港口水域LNG罐箱运输定量风险评价

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天然气工业 2009年第1期29卷 114-116页

作者：张青松天津大学管理学院

船载LNG罐箱在航道拥挤的港口水域内运输为一动态危险源,一旦发生事故涉及面广,危害严重。基于定量风险评价的基本原理及公路危险化学品罐车运输定量风险评价,结合港口水域船舶运输特点,提出了港口水域船载LNG罐箱运输定量风险评价的一... 详细信息

船载LNG罐箱在航道拥挤的港口水域内运输为一动态危险源,一旦发生事故涉及面广,危害严重。基于定量风险评价的基本原理及公路危险化学品罐车运输定量风险评价,结合港口水域船舶运输特点,提出了港口水域船载LNG罐箱运输定量风险评价的一般方法,并构建了个人风险和社会风险计算模型。以某两个港口水域LNG罐箱船舶运输为例:由个人风险等值线可知LNG罐箱在两港口水域内运输的个人风险等级均在10-9～10-7之间,相当于自然灾害的风险;由社会风险曲线可知,死亡人数大于或等于N的累积频率在10-8～10-5之间,即在可接受风险标准线和不可接受风险标准线之间的区域;通过两个港口个人风险和社会风险对比分析,不仅可为LNG罐箱水路运输路线优化选择提供定量依据,而且对于港口水域LNG罐箱运输风险分析、安全管理及应急预案的制定等都具有实际意义。

关键词：液化天然气罐式集装箱定量风险分析数学模型港口水域

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Development and optimization of an intergeneric conjugation system and analysis of promoter activity in Streptomyces rimosus M527

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第11期20卷 891-900页

作者： zhang-qing song Zhi-jun LIAO Ye-feng HU Zheng MA Andreas BECHTHOLD Xiao-ping YU Zhejiang Provincial Key Laboratory of Biometrology and Inspection&Quarantine College of Life SciencesChina Jiliang UniversityHangzhou 310018China Institute for Pharmaceutical Sciences Pharmaceutical Biology and BiotechnologyUniversity of Freiburg79104 FreiburgGermany

An efficient genetic transformation system and suitable promoters are essential prerequisites for gene expression studies and genetic engineering in *** this study,firstly,a genetic transformation system based on intergeneric conjugation was developed in Streptomyces rimosus M527,a bacterial strain which exhibits strong antagonistic activity against a broad range of plant-pathogenic *** experimental parameters involved in this procedure were optimized,including the conjugative media,ratio of donor to recipient,heat shock temperature,and incubation time of mixed *** the optimal conditions,a maximal conjugation frequency of 3.05^10-5 per recipie nt was obtai *** ntly,based on the above developed and optimized tran sformati on system,the synthetic promoters SPL-21 and SPL-57,a native promoter potrB,and a constitutive promoter permE commonly used for gene expression in streptomycetes were selected and their activity was analyzed using gusA as a reporter gene in *** *** the four tested promoters,SPL-21 exhibited the strongest expression activity and gave rise to a 2.2-fold increase in p-glucuronidase(GUS)activity compared with the control promoter *** SPL-57 showed activity comparable to that of *** potrB,which showed the lowest activity,showed a 50%decrease in GUS activity compared with the control *** transformation system developed in this study and the tested promotors provide a basis for the further modification of *** M527.

关键词： Streptomyces rimosus M527 Intergeneric conjugation Promoter β-Glucuronidase(GUS)

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