检索结果-南通市图书馆

ELIMINATION IN WEYI ALGEBRA AND q-IDENTITIES

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2007年第4期20卷 601-609页

作者： yujuan huang Tianming WANG Department of Mathematics & Physics Shandong Jiaotong University Jinan 250023 China Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

In this paper, the following are introduced briefly： the basic concept of q-proper-hypergeometric; an algorithmic proof theory for q-proper-hypergeometric identities; and elimination in the non- commutative Weyl algebra. We give an algorithm for proving the single-variable q-proper-hypergeometric identities that is based on Zeilberger＇s approach and the elimination in Weyl algebra. Finally, we test several examples that have been proven by D. Zeilberger and H. Will using the WZ-pair method and Gosper algorithm.

关键词： Algorithm proof elimination q-hypergeometric identities.

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

尾缘切除对低压涡轮叶栅气动性能的影响

大连海事大学学报 2024年第1期50卷 158-166页

作者：付星豪黄玉娟马志乐韦文涛中国航发沈阳发动机研究所沈阳110000

选取某低压涡轮导向叶片中截面叶型作为研究对象,采用数值模拟方法研究尾缘切除对低压涡轮叶栅气动性能的影响,研究切除长度分别为2.5%、5.0%、7.5%弦长时叶栅气动性能的变化,并且采用尖边倒圆、将尾缘修整为圆弧形、椭圆形三种方式对... 详细信息

选取某低压涡轮导向叶片中截面叶型作为研究对象,采用数值模拟方法研究尾缘切除对低压涡轮叶栅气动性能的影响,研究切除长度分别为2.5%、5.0%、7.5%弦长时叶栅气动性能的变化,并且采用尖边倒圆、将尾缘修整为圆弧形、椭圆形三种方式对切尾缘后叶型剩余尾部进行修型。结果表明:尾缘切除可有效增加叶栅槽道的流通能力,并且流通能力随尾缘切除长度增加而增加;切尾缘后叶栅损失增大,并且与尾缘切除长度呈正相关;切尾缘后的修型方式会对叶栅损失水平产生影响,将尾缘修整为椭圆形对损失抑制效果最明显,在同样切除长度下其尾迹损失和端区损失均低于另外两种修型方式;尾缘切除对叶栅出口气流角影响微弱,尾缘切除长度每增加1%弦长,三种修型方式叶栅出口气流角增加量为0.13°~0.16°。

关键词：低压涡轮(LPT) 叶栅气动性能导向叶片尾缘切除

个体化护理在ICU重症肺炎患者中的应用效果分析

在线全文

学校读者我要写书评

暂无评论

中外医疗 2024年第17期43卷 159-162页

作者：黄玉娟顾芸芬孟徐蕾上海交通大学医学院附属瑞金医院重症医学科上海200000

目的探究对重症加强护理病房(Intensive Care Unit,ICU)中重症肺炎患者开展个性化护理的应用价值。方法前瞻性单纯方便选取上海交通大学医学院附属瑞金医院ICU于2022年8月—2023年11月收治的77例重症肺炎患者为研究对象,以随机数字表... 详细信息

目的探究对重症加强护理病房(Intensive Care Unit,ICU)中重症肺炎患者开展个性化护理的应用价值。方法前瞻性单纯方便选取上海交通大学医学院附属瑞金医院ICU于2022年8月—2023年11月收治的77例重症肺炎患者为研究对象,以随机数字表法分为两组,对照组(n=33)实施常规化护理,观察组(n=34)实施个体化护理,对比两组自我护理能力、舒适感受及护理满意度。结果护理后,两组自我护理能力评分、舒适状况量表评分较护理前得到显著改善,且观察组高于对照组,差异有统计学意义(P均<0.05)。观察组护理满意度为97.06%,高于对照组的75.76%,差异有统计学意义(χ^(2)=4.831,P<0.05)。结论经个体化护理,ICU重症肺炎患者的自我护理能力、舒适度及满意度有了明显提高。

关键词：个体化护理重症加强护理病房重症肺炎舒适度

维普期刊数据库博看期刊

儿童糖尿病酮症酸中毒的临床特征及相关影响因素分析

在线全文

学校读者我要写书评

暂无评论

临床儿科杂志 2024年第4期42卷 333-338页

作者：王静刘莉程安娜王韧健陈婷婷许秀何黄玉娟上海市儿童医院、上海交通大学医学院附属儿童医院急诊科上海200062 上海市北医院儿科上海200435

目的探讨以糖尿病酮症酸中毒(DKA)起病的新发1型糖尿病(T1DM)儿童的临床特征及相关影响因素,以提高临床医师对DKA高危患儿的早期识别,改善DKA患儿生存预后。方法回顾性分析2015年1月1日至2021年12月31日收治的214例新发T1DM的患儿资料,... 详细信息

目的探讨以糖尿病酮症酸中毒(DKA)起病的新发1型糖尿病(T1DM)儿童的临床特征及相关影响因素,以提高临床医师对DKA高危患儿的早期识别,改善DKA患儿生存预后。方法回顾性分析2015年1月1日至2021年12月31日收治的214例新发T1DM的患儿资料,分为DKA组和NDKA组,比较两组临床特征及实验室检查。采用多因素logistic回归分析儿童DKA发生的相关影响因素。结果214例新发T1DM患儿,DKA组110例(51.4%),NDKA组104例(48.6%)。多饮、多尿、多食、体重减轻等典型糖尿病症状多见于NDKA组,胃肠道症状、神经精神状态改变、脱水症等多见于DKA组(P<0.05)。将单因素分析有意义的变量(年龄、前驱感染、症状持续时间、血浆C肽、血糖)进一步纳入多因素logistic回归分析显示,前驱感染(OR=7.541,95%CI:3.315~17.151),症状持续时间(OR=0.989,95%CI:0.980~0.999),血清C肽(OR=3.044,95%CI:1.571~5.899)和血糖(OR=5.652,95%CI:2.582~12.373)是儿童DKA发生的独立影响因素。结论T1DM患儿具有前驱感染、症状持续时间短、低血浆C肽和高血糖应警惕发展为DKA。

关键词： 1型糖尿病糖尿病酮症酸中毒影响因素儿童

Refinement of Methodology for Cadmium Determination in Soil Micro-Arthropod Tissues

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2017年第3期27卷 491-501页

作者： ZHU Dong KE Xin WU Longhua huang yujuan Peter CHRISTIE LUO Yongming Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Key Laboratory of Coastal Zone Environmental Processes Yantai Institute of Coastal Zone Research Chinese Academy of Sciences

Highly precise and reliable determination of heavy metals in soil micro-arthropod tissues remains a challenge because of the small size of the animals and their typical low abundance in metal-contaminated agricultural soils. The present study sought to develop a method for cadmium （Cd） determination in soil micro-arthropods by optimizing the sample digestion procedure, reducing sample weight, modifying sample pre-treatment and validating the methodology with field samples. The optimized digestion conditions comprised a sample mass of 50-150 μg, digestion reagent of nitric acid：hydrogen peroxide （3：1）, digestion temperature of 105 ℃, digestion period of 3 h and digestion volume of 30 μL. Defecation of the standard Collembola Folsomia candida （92 h） and the indigenous Collembola Onychiurus yodai （42 h） and ultrasonic cleaning of F. candida increased the accuracy of Cd determination. The recovery of Cd using the refined procedure was 98.9% and the limits of detection and quantification were 0.002 and 0.008 μg L-1, respectively. The within-batch precision values were 〈 3%. The Cd concentrations in the tissues of the Collembola Isotorna sp. collected from a range of metal-contaminated fields determined by the improved method were consistent with the Cd concentrations in the field soils. The results indicate that the optimized method can be used for more accurate or reliable determination of Cd concentrations in soil micro-arthropod tissues.

关键词： digestion defecation Folsomia candida micro-samples predatory mite sample pre-treatment ultrasonic cleaning

基于多源数据的综合交通优势度与科技创新产业的空间交互关系

在线全文

学校读者我要写书评

暂无评论

山东交通学院学报 2024年第2期32卷 97-107页

作者：黄玉娟樊丹丹姜勇张伟华山东交通学院交通与物流工程学院山东济南250357

为分析山东省综合交通优势度与科技创新产业间的耦合协调关系,基于多源数据,梳理交通枢纽点、线、面特性及综合运输能力,构建综合交通优势度模型;基于政府支出、产业规模、创新产出3要素构建科技创新产业集聚度模型,定量分析山东省16个... 详细信息

为分析山东省综合交通优势度与科技创新产业间的耦合协调关系,基于多源数据,梳理交通枢纽点、线、面特性及综合运输能力,构建综合交通优势度模型;基于政府支出、产业规模、创新产出3要素构建科技创新产业集聚度模型,定量分析山东省16个地级市的综合交通优势度与科技创新产业集聚度的空间分布格局、耦合协调水平和关联影响因素。结果表明:山东各地级市的综合交通优势度与科技创新产业集聚度有明显的空间分布差异,呈以青岛-济南为双核心的散射状空间发展格局;二者的协调水平有明显的空间相关性,存在显著的集聚模式;胶东经济圈、省会经济圈、鲁南经济圈的综合交通优势度与科技创新产业集聚度呈梯度下降式分布;构建多元化的交通网络系统可有效促进区域多式联运,政府支持率是区域科技创新产业规模和产出的直接影响因素;交通优势度与科技创新产业存在明显的正向影响关系,航空运输对科技创新产业的影响最显著;交通建设与科技产业的发展相互促进,交通发展吸引科技创新产业集聚,科技创新产业发展促使交通延伸,二者发展一致,达到高度协调时,产生空间溢出效应,带动周围地区社会经济发展,形成区域一体化的协调发展空间格局。

关键词：交通优势度科技创新产业产业集聚度耦合协调度

Adsorption and desorption characteristics of diphenylarsenicals in two contrasting soils

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第6期25卷 1172-1179页

作者： Anan Wang Shixin Li Ying Teng Wuxin Liu Longhua Wu Haibo Zhang yujuan huang Yongming Luo Peter Christie Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences Graduate School of Chinese Academy of Sciences Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Agri-Environment Branch Agri-Food and Biosciences InstituteNewforge LaneBelfast BT9 5PXUK

Diphenylarsinic acid （DPAA） is formed during the leakage of aromatic arsenic chemical weapons in soils, is persistent in nature, and results in arsenic contamination in the field. The adsorption and desorption characteristics of DPAA were investigated in two typical Chinese soils, an Acrisol （a variable-charge soil） and a Phaeozem （a constant-charge soil）. Their thermodynamics and some of the factors influencing them （i.e., initial pH value, ionic strength and phosphate） were also evaluated using the batch method in order to understand the environmental fate of DPAA in soils. The results indicate that Acrisol had a stronger adsorption capacity for DPAA than Phaeozem. Soil DPAA adsorption was a spontaneous and endothermic process and the amount of DPAA adsorbed was affected significantly by variation in soil pH and phosphate. In contrast, soil organic matter and ionic strength had no significant effect on adsorption. This suggests that DPAA adsorption may be due to specific adsorption on soil mineral surfaces. Therefore, monitoring the fate of DPAA in soils is recommended in areas contaminated by leakage from chemical weapons.

关键词： diphenylarsinic acid adsorption and desorption chemical weapons residual soil contamination

Sequence [2,3]-Sigmatropic Rearrangement: One-Pot Synthesis of Proparggyl Allenylamines

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第18期42卷 2223-2227页

作者： Huihui Feng yujuan Xie Lliang huang Yongqing Xu Junhai huang huangdi Feng College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Frontiers Science Research Centerfor Druggability of Cardiovascular noncoding RNA Institute for Frontier Medical Technology Shanghai Universityof Engineering ScienceShanghai 201620China

Allenes,served as highly sought-after building blocks,are an indispensable component of synthetic *** utility in modulating the chemical,physical,and pharmaceutical properties of organic compounds make allenes a desirable choice in various ***,we report a facile method for the atom-economical synthesis of propargyl allenylamines via an underdeveloped[2,3]-sigmatropic *** strategy employs easily accessible propargylamines as starting materials,which are first converted into propargyl ammonium salts,followed by a base-promoted[2,3]-sigmatropic *** one-pot,two-step reaction proceeds in the absence of transition metals,displays a very broad scope,and does not require the introduction of the electron-withdrawing group into the starting materials.

关键词： Allene Propargylamine C-N activation Sigmatropic rearrangement Metal-free Synthetic methods Domino reactions

A commentary of“Mechanism of alkaline tolerance and application in crop improvement”:Top 10 Chinese Scientific Advances of 2023,China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fundamental Research 2024年第3期4卷 697-698页

作者： yujuan Zhu Sanwen huang Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong 518120China State Key Laboratory of Tropical Crop Breeding Chinese Academy of Tropical Agricultural SciencesHaikouHainan 571101China

As global warming accelerates,soil degradation,exacerbated by extreme weather,has become a significant environmental issue ***,in particular,is grappling with a yearly reduction in arable land due to soil degradation,acidification,and salinization,posing potential threats to food *** country has a vast area of saline-alkaline land,over half of which are high-pH soda saline *** lands often experience simultaneous salt and alkali stress,severely inhibiting plant growth and crop ***,finding ways to utilize this marginal and saline-alkaline land for food production is a critical scientific *** this context,Chinese scientists have achieved a breakthrough towards harnessing saline-alkaline land.

关键词： alkaline utilize breakthrough