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Ecological effect of the plantation of Sabina vulgaris in the Mu Us Sandy Land,China

Journal of Arid Land 2024年第1期16卷 14-28页

作者： NAN Weige DONG Zhibao ZHOU Zhengchao LI Qiang chen guoxiang School of Geography and Tourism Shaanxi Normal UniversityXi'an 710062China Shaanxi Key Laboratory of Ecological Restoration in Shaanbei Mining Area Yulin UniversityYulin 719000China College of Prataculture Gansu Agricultural UniversityLanzhou 730070China

Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid *** study aimed to explore the ecological effect of the plantation of Sabina vulgaris on soil physical and chemical properties on the southeastern fringe of the Mu Us Sandy Land,*** collected soil samples from five depth layers(0-20,20-40,40-60,60-80,and 80-100 cm)in the *** plantation plots across four plantation ages(4,7,10,and 16 years)in November 2019,and assessed soil physical(soil bulk density,soil porosity,and soil particle size)and chemical(soil organic carbon(SOC),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),available potassium(AK),cation-exchange capacity(CEC),salinity,p H,and C/N ratio)*** results indicated that the soil predominantly consisted of sand particles(94.27%-99.67%),with the remainder being silt and *** plantation age increased,silt and very fine sand contents progressively *** 16 years of planting,there was a marked reduction in the mean soil particle *** initial soil fertility was low and declined from 4 to 10 years of planting before witnessing an *** positive correlations were observed for the clay,silt,and very fine sand(mean diameter of 0.000-0.100 mm)with SOC,AK,and p *** contrast,fine sand and medium sand(mean diameter of 0.100-0.500 mm)showed significant negative correlations with these *** findings ascertain that the plantation of *** requires 10 years to effectively act as a windbreak and contribute to sand fixation,and needs 16 years to improve soil physical and chemical ***,these improvements were found to be highly beneficial for vegetation restoration in arid and semi-arid *** research can offer valuable insights for the protection and restoration of the vegetation ecosystem in the sandy lands in China.

关键词： Sabina vulgaris plantation age soil physical and chemical properties soil particle size soil fertility vegetation restoration Mu Us Sandy Land

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Rheological Behavior of Semi-Solid AZ91D Magnesium Alloy at Steady State

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Journal of Wuhan University of Technology(Materials Science) 2015年第1期30卷 162-165页

作者：闫洪 RAO Yuansheng chen guoxiang School of Mechanical and Electrical Engineering Nanchang University

The rheological behavior of semi-solid AZ91D magnesium alloy was investigated in isothermal steady state condition. The effects of stirring temperature and shearing rate on apparent viscosity of semi-solid alloy slurry at steady state were discussed. The results show that the apparent viscosity of semisolid AZ91D alloy increases with increasing solid fraction. It increases slightly before the solid fraction reaches a certain value, about 0.4, and then goes up rapidly aider the solid fraction reaches the critical value. However, the apparent viscosity decreases with increasing shearing rate, and the reduction amplitude is higher when the solid fraction is higher. According to the experimental data, an empirical equation that shows the effect of solid fraction and sheafing rate on the apparent viscosity of semi-solid AZ91D alloy can be built as ηa=9.7×10^-2 exp（13.87fs）γ^-0.58.

关键词： semi-solid magnesium alloy apparent viscosity solid fraction shearing rate

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支持关键词搜索的top-K条最优路线查询问题

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计算机应用 2024年第8期44卷 2455-2465页

作者：赵浩宇于自强陈晓萌陈国祥朱慧李博涵烟台大学计算机与控制工程学院山东烟台264005 南京航空航天大学计算机科学与技术学院南京211106

支持关键词搜索的top-K条最优路线查询问题是针对给定的道路网络、兴趣点集合、起点和多个关键词的路线查询。查询旨在找到途经与查询关键词匹配的多个兴趣点的k条最优路线。然而,一些现有研究为降低算法的复杂度,将用户输入关键词的顺... 详细信息

支持关键词搜索的top-K条最优路线查询问题是针对给定的道路网络、兴趣点集合、起点和多个关键词的路线查询。查询旨在找到途经与查询关键词匹配的多个兴趣点的k条最优路线。然而,一些现有研究为降低算法的复杂度,将用户输入关键词的顺序作为到达兴趣点顺序,不适用于对兴趣点到达顺序没有要求的场景,降低了实用性;另一些研究为提高查询效率,设定距离阈值对不符合要求的兴趣点剪枝,然而这类算法无法保证被剪枝的兴趣点一定不能组成最优路线。针对上述问题,提出一种关键词感知的top-K最优路线搜索(KKRS)算法。首先,将整个道路网络划分为多个子网络。然后,采用启发式搜索策略从查询起点所在的子网络开始逐步扩展搜索范围,直至找到top-K条最优路线或遍历完整个道路网络。在扩展过程中,引入子图剪枝策略,用于剪去不包含top-K最优路线的子网络,缩小搜索范围。此外,为避免对每个可能构成最优路线的兴趣点集合依次计算,设计兴趣点序列的剪枝策略,以快速过滤不可能构成最优路线的兴趣点序列,降低计算代价。最后,在真实数据集和合成数据集上对提出的两种剪枝算法进行实验,实验结果表明这两种算法在所有数据集上的子图剪枝上都能达到70%以上的剪枝率,在兴趣点序列剪枝上则能保证60%以上的剪枝率。与目前已有的先进算法大规模路网图下关键词覆盖最优路径查询(KORL)、ROSE-GM(Recurrent Optimal Subroute Expansion Using Greedy Merge Strategy)、OSSCaling和StarKOSR(finding Top-K Optional Sequenced Routes with A*)相比,KKRS算法比对比算法中查询效率较高的StarKOSR算法提高了40%。

关键词：道路网络路线剪枝兴趣点关键词搜索个性化旅游路线

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STRONGLY CONTINUOUS INTEGRATED COSINE OPERATOR FUNCTIONS WITH GROWTHω

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Analysis in Theory and Applications 2007年第1期23卷 1-8页

作者： Meiying Wang guoxiang chen Department of Mathematics Nanjing Audit University Nanjing 210029 P. R. China

For a continuous increasing function ω ： [0, ∞） → （0, ∞） of finite exponetial type, we establish a Hille-Yosida type theorem for strongly continuous integrated cosine operator functions with O（ω）. It includ... 详细信息

关键词： cosine operator functions with growth ω generator generation theorem

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MAXIMAL SUBSPACES FOR SOLUTIONS OF THE SECOND ORDER ABSTRACT CAUCHY PROBLEM

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Analysis in Theory and Applications 2007年第3期23卷 266-273页

作者： guoxiang chen Meiying Wang Department of Applied Mathematics Audit University Nanjing 210029P. R. China

For a continuous, increasing function ω ： R^＋ →R^＋／{0} of finite exponential type, this paper introduces the set Z（A, ω） of all x in a Banach space X for which the second order abstract differential equation （2） has a mild solution such that [ω（t）]^-1u（t,x） is uniformly continues on R^＋, and show that Z（A, ω） is a maximal Banach subspace continuously embedded in X, where A ∈ B（X） is closed. Moreover, A[z（A,ω） generates an O（ω（t）） strongly continuous cosine operator function family.

关键词： second order abstract cauchy problem solution with growth ω cosine operator function family

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Influence of salinity and moisture on the threshold shear velocity of saline sand in the Qarhan Desert, Qaidam Basin of China: A wind tunnel experiment

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Journal of Arid Land 2019年第5期11卷 674-684页

作者： LI Chao DONG Zhibao YIN Shuyan chen guoxiang YANG Junhuai College of Geography and Tourism Shaanxi Normal University

Determination of the threshold shear velocity is essential for predicting sand transport,dust release and *** this study,a wind tunnel experiment was conducted to evaluate the influence of salinity and moisture on the threshold shear velocity of saline *** sand samples(mean particle size of 164.50–186.08μm and the total silt,clay and salt content of 0.80%–8.25%)were collected from three saline sand dunes(one barchan dune and two linear dunes)in the Qarhan Desert,Qaidam Basin of *** saline sand samples were placed in two experimental trays for wet and dry processing to simulate deliquescence and desiccation,*** moisture content ranging from 0.30% to 1.90% was generated by the steam method so that the saline sand can absorb water in a saturated water vapor *** motion of sand particles was determined by the observers with a solid *** laser sheet(0.80 cm thick),which was emitted by the solid laser,horizontally covered the sand surface and was bound to the *** show that the cohesion of saline sand results from a combination of salt and *** threshold shear velocity increases exponentially with the increase in crust thickness for the linear sand *** is a positive linear correlation between the original moisture content and relative threshold shear *** threshold shear velocity of dewatered sand is greater than that of wet sand with the same original moisture *** results will provide valuable information about the sand transport of highly saline soil in the desert.

关键词： threshold shear velocity saline sand barchan dune linear dune crust thickness moisture content Qaidam Basin

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Pancreatic cancer–Palliative therapy: surgery (bypass/resection)

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The Chinese-German Journal of Clinical Oncology 2007年第2期6卷 133-137页

作者： Xiaoping chen guoxiang Yao Department of Surgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective: We compare the outcome of palliative pancreaticoduodenectomy and palliative surgical bypass in patients with advanced pancreatic carcinoma in our hospital. Recent published related articles are also reviewed. Methods: A respective analysis was performed comparing the perioperative parameters and outcome of 20 patients who underwent pancreaticoduodenectomy with a gross suspected cancer residue and 30 patients who underwent a surgical bypass, all of the patients were diagnosed as in advanced stages intra-operatively. Results: The two groups were comparable with patient characteristics, including age, gender, initial symptoms and concomitant major organ diseases. Tumors are similar in size and intra-operatively diagnosed as in advanced stages in both groups. All of the patients in the resection group were microscopically proved having cancer residue. One postoperative mortality occurred in the resection group (5%), zero in the bypass group (P > 0.05). Overall complications were significantly higher in the resection group (30% vs. 0, P < 0.01), including 2 patients developed Acute Respiratory Distress Syndrome (ARDS), zero in the bypass group (P < 0.01); hemorrhage and transfusions in the resection group were much more than that in the bypass group (P < 0.05). Hospital stay after resection was significantly longer than bypass (20 vs. 12 days, P < 0.01). Hospital fee after resection was 4 times more than after bypass (median 61.500 vs. 15. 300 yuan, P < 0.01). Survival was significantly longer after resection (median 12.2 vs. 7.1 months, P < 0.01). Conclusion: Our results show that palliative resection in advanced pancreatic carcinoma lengthens the survival time of the patients, but this is paid for significantly higher complications than bypass.

关键词： pancreatic cancer palliative advanced surgery

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5种农药对梨小食心虫的室内毒力测定及田间药效评价

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新疆农业科学 2024年第3期61卷 665-671页

作者：魏杨陈国祥阿地力·沙塔尔买买托合提·吐孙田光宇新疆农业大学林学与风景园林学院乌鲁木齐830052 新疆和田县林业和草原局新疆和田848000

【目的】筛选出对梨小食心虫具有较强防效的农药。【方法】采用生测法和喷雾法分别测定5种农药对梨小食心虫的室内毒力和评价田间药效。【结果】5%甲维盐·虱螨脲对梨小食心虫的3龄幼虫的毒力最高,其LC 50值为4.12 mg/L,其次为10%高效... 详细信息

【目的】筛选出对梨小食心虫具有较强防效的农药。【方法】采用生测法和喷雾法分别测定5种农药对梨小食心虫的室内毒力和评价田间药效。【结果】5%甲维盐·虱螨脲对梨小食心虫的3龄幼虫的毒力最高,其LC 50值为4.12 mg/L,其次为10%高效氯氟氰菊酯、14%氯虫·高氯氟和10%氯虫苯甲酰胺,LC 50值分别为8.23、15.14和16.07 mg/L;25%甲维·灭幼脲毒力最低,LC 50值为40.65 mg/L;10%氯虫苯甲酰胺1000倍稀释液和5%甲维盐·虱螨脲2000倍稀释液对幼虫毒杀效果最好,处理24 h后,对幼虫校正死亡率均达到85%以上,72 h时达到100%。10%氯虫苯甲酰胺和5%甲维盐·虱螨脲的速效性最好,田间施药1 d后,防效能达到60%以上。施药后5 d,防效分别为87.72%和82.46%,显著高于其他农药。【结论】10%氯虫苯甲酰胺和5%甲维盐·虱螨脲对和田县桃树栽植区梨小食心虫幼虫具有较好的控制效果。

关键词：梨小食心虫室内毒力测定田间药效评价

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梨小食心虫在桃树和核桃间转移规律初步研究

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植物保护 2024年第1期50卷 280-285页

作者：魏杨陈国祥李佩璇阿地力•沙塔尔图尔迪麦麦提•努尔麦麦提新疆农业大学林学与风景园林学院乌鲁木齐830052 新疆农业大学园艺学院乌鲁木齐830052 新疆和田县拉依喀乡林业站和田848000

为了掌握梨小食心虫Grapholita molesta在新疆和田县桃园和核桃园间的转移为害和种群动态变化规律,以期确定核桃园内梨小食心虫的最佳防治时间,同时在桃园和核桃园设立监测点,通过对梨小食心虫在桃园和核桃园间的发生动态监测以及在核... 详细信息

为了掌握梨小食心虫Grapholita molesta在新疆和田县桃园和核桃园间的转移为害和种群动态变化规律,以期确定核桃园内梨小食心虫的最佳防治时间,同时在桃园和核桃园设立监测点,通过对梨小食心虫在桃园和核桃园间的发生动态监测以及在核桃园内产卵情况和蛀果率调查,明确了梨小食心虫在桃园和核桃园间的转移规律。研究发现梨小食心虫在和田县桃园1年发生5代,越冬代成虫于3月下旬开始出现,各代高峰期分别在4月上旬、5月中旬、6月下旬至7月上旬、7月下旬至8月上旬、9月上旬,以第1代和第2代发生为害严重,具有世代重叠现象。梨小食心虫在核桃园1年发生2代,成虫产卵于核桃果实和叶片,主要以幼虫为害果实。于6月下旬开始从桃园向核桃园转移,8月下旬又从核桃园转移至桃园,具有明显的寄主转移规律。7月初为核桃园内梨小食心虫的防治关键期。

关键词：梨小食心虫发生动态寄主转移桃核桃

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Dual-phase coexistence enables to alleviate resistance drift in phase-change films

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Journal of Semiconductors 2024年第7期45卷 55-59页

作者： Tong Wu chen chen Jinyi Zhu guoxiang Wang Shixun Dai Laboratory of Infrared Materials and Devices The Research Institute of Advanced TechnologiesNingbo UniversityNingbo 315211China Institute of Ocean Engineering Ningbo UniversityNingbo 315211China

The amorphous phase-change materials with spontaneous structural relaxation leads to the resistance drift with the time for phase-change neuron synaptic devices. Here, we modify the phase change properties of the conventional Ge_2Sb_2Te_5(GST) material by introducing an SnS phase. It is found that the resistance drift coefficient of SnS-doped GST was decreased from 0.06 to 0.01. It can be proposed that the origin originates from the precipitation of GST nanocrystals accompanied by the precipitation of SnS crystals compared to single-phase GST compound systems. We also found that the decrease in resistance drift can be attributed to the narrowed bandgap from 0.65 to 0.43 eV after SnS-doping. Thus, this study reveals the quantitative relationship between the resistance drift and the band gap and proposes a new idea for alleviating the resistance drift by composition optimization, which is of great significance for finding a promising phase change material.

关键词： phase change films X-ray methods resistance drift optical band gap

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