检索结果-南通市图书馆

Journal of Leather Science and engineering 2021年第1期3卷 337-349页

作者： monica gisel Arellano‑Sanchez Christine Devouge‑Boyer marie Hubert‑Roux Carlos Afonso melanie mignot UNIROUeN COBRA UMR CNRS 6014INSANormandie UniversityAvenue de l’Universite76800 Saint‑Etienne‑du‑RouvrayFrance UNIROUeN COBRAUMR CNRS 6014IRCOFNormandie University76821 Mont‑Saint‑Aignan CedexFrance

In this study,seven pretreatment methods for chromium speciation in tanned leather were evaluated:acidic miner‑alization,ethylenediaminetetraacetic acid(eDTA)extraction,diethylenetriaminepentaacetic acid(DTPA)extraction,alkaline extraction(NH 4 OH),ammonium nitrate extraction(NH 4 NO 3),water extraction,and phosphate buffer extrac‑*** mineralization permitted the decomposition of the organic matter and ensured the complete digestion of leathers,giving access to the total content of chromium in each sample using inductively coupled plasma‑atomic emission spectrometry(ICP‑AeS).From all the extractant media tested,eDTA proved to be the most efficient,allowing the extraction of Cr(VI)and Cr(III)as a Cr(III)‑eDTA complex,*** validation is presented for eDTA extraction and direct *** the eDTA extraction,method detection limit(mDL)and method quantifica‑tion limit(mQL)for total Cr in leather were 3.4 ppb and 11.2 ppb(µg of total Cr per L of extraction solution),respec‑*** to the lack of leather certified reference materials(CRms)for Cr(VI),accuracy was evaluated by spiking leather samples with a Cr(VI)*** spike recovery of eDTA microwave assisted extraction ranged from 91.0 to 108.6%.Interday precision was also evaluated and all variation coefficients were below 5%,for both mineralization and eDTA *** article provides an efficient procedure to extract quantitatively chromium from leather,while maintaining the speciation,which can be further followed by ion chromatography‑inductively coupled plasma‑mass spectrometry(IC‑ICP‑mS).

关键词： Hexavalent chromium Speciation Tanned leather Sample pretreatment eDTA complexation Inductively coupled plasma

Preliminary Results from the TCABR Tokamak

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国核科技报告 1999年第S4期 391-391页

作者： I.C.Nascimento,R.m.O.galvo,A.N.Fagundes,e.K.Sanada,Y.Kuznetsov,A.P.dos Reis,F.T.Degasperi,N.A.m.Cuevas,J.I.elizondo,A.g.Tuszel,R.P.da Silva,D.Campos,W.P.de S,J.H.Vuolo,A.Vannucci,L.Ruchko,N.R.Nunes,V.S.W.Vuolo,m.V.A.P.Heller C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 Instituto de Física Universidade de So Paulo SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo SP-Brazil C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 Instituto de Física Universidade de So Paulo SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo C.P. 66318 So Paulo 05315-970 SP-Brazil 05315-970 SP-Brazil Instituto de Física Universidade de So Paulo

After a long period of assembling and repairing faulty components, tokamak discharges started this year to be routinely obtained in TCABR. TCABR was brought from Lausanne-Switzerland some years ago. It is a middle siz... 详细信息

关键词： this Preliminary Results from the TCABR Tokamak

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

地中海及其邻区的上地幔速度结构

地球物理学进展 1992年第1期7卷 105-105页

作者： V.g.Krishna 柯忍

本文仔细地分析了深达500km的229个深震的P波和S波走时资料,取得了地中海及其邻区的上地幔速度结构.用Kaila(1969)分析法得到卡拉布里亚孤—第勒尼安海、西地中海—南西班牙、巴尔干半岛的西缘和东缘以及东喀尔巴阡山脉的Vrancea区的中... 详细信息

本文仔细地分析了深达500km的229个深震的P波和S波走时资料,取得了地中海及其邻区的上地幔速度结构.用Kaila(1969)分析法得到卡拉布里亚孤—第勒尼安海、西地中海—南西班牙、巴尔干半岛的西缘和东缘以及东喀尔巴阡山脉的Vrancea区的中、深源地震区的“震源深度上”的P波和S波速度.显示出直到150km深度的地段,其横向速度变化约为3%一4%.巴尔干边缘的尸波速度为最高.在卡拉布里亚孤一第勒尼安海深震区,p波速度由40 km深度上8.01 km/s增加到2,0 km深度上的8.14 km/5.尸波速度从具变化率为0,0055一,的210 km较深部起迅速地增加,到500 km深度上.达到9.62 km/5.该区的S波速度由40k。深度上的458 km/s增加到400 km深度上的4.73 km/:,没有任何关于快速的速度增加带的象征.然而,发现了卡拉布里亚孤一第勒尼安海深震区的S波速度比由面波频散研究导出的邻区的上地慢顶部150一200 km区段的平均S波速度4.34 km/s高出约6%.与此类似,西地中海和巴尔干边缘的中源地震区,其S波速度比邻区上地慢相应的平均值高约5%.这些差异本质上是因为存在一条轮廓清晰的扩展到中欧大部地区的次盖层(sub一lid))低S波速通道引起的.本文确定的卡拉布里亚弧一第勒尼安海深震区的尸波速度模型显然与eKw的p波速度模型(england等,1 077)和mR的速度模型(mager一Rosa和mue]ler.1 973)+分一致,这两个模型适用于南一中欧下方的上地慢区域、把南一中欧的尸波速度模型,包括本文提出的模型,与适合于东欧地台下方的上地慢p波速度模型,即sNF(Hurtig等,1979),KCA(King和Caxeagnile,197e)和m^(masse和Alexander,1974)模型相比较,揭示出这两区的上地慢具有强烈的横向速度不均匀性.南一中欧的速度比东欧地台的速度约低5%,这种情况到至少250 km的深度上都存在.这些结果与stromeyer(1 978)给出的欧洲温度一深度函数一致,Stromcyer(1 978)指出中欧的这些深度上的温度比东欧地台的高400一500℃.本文确定的卡拉布里亚孤一第勒尼安海深震区,从40一400 km深度,其S波速度(4,6一4.7 km/s)几乎不变.也是与所预计的中欧下方的邻近上地慢区具较高温度相一致.在本研究中,尸波和S波速度模型,直到深达500 km都未发现“400 km间断”,这可能是因为在南一中欧,它在520一540 km这个比较大的深度上,而其它几个模型给出,在东欧地台区它在380一420 km的深度上,比较之下相对较浅.另一方面,210一500 km深度上的高尸波速度梯度可以说明不存在“明显的”400 km间断。

关键词：波速度速度模型速度结构上地幔横向速度变化速度比第勒尼安海地台频散面波

维普期刊数据库

Natural variation of main biochemical components,morphological and yield traits among a panel of 87 tea [Camellia sinensis(L.) O. Kuntze] cultivars

在线全文

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2023年第3期9卷 563-576页

作者： Fawad Zaman eZhang Li Xia Xielong Deng muhammad Ilyas Ahmad Ali Fei guo Pu Wang mingle Wang Yu Wang Dejiang Ni Hua Zhao Key Laboratory of Horticultural Plant Biology of ministry of education Huazhong Agricultural UniversityWuhanHubei 430070China College of Horticulture and Forestry Sciences Huazhong Agricultural UniversityWuhanHubei 430070China College of Plant Science and Technology Huazhong Agricultural UniversityWuhanHubei 430070China

many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm has not been adequately evaluated. In this study, the main biochemical components, leaf morphological and yield characteristics were evaluated for four rounds of tea leaves in a panel of 87 elite tea cultivars suitable for black, green, or oolong tea. Significant variations were observed among the tea cultivars, as well as seasonal differences in the levels of the free amino acid(FAA), caffeine(CAF), tea polyphenols(TP), water extract(We) and TP to FAA ratio(TP/FAA). Results showed that the average levels of FAA showed a seasonal change, with the highest level of 4.0% in the 1st spring tea in the cultivars suitable for green tea and the lowest of 3.2% in summer tea in the cultivars suitable for black tea. The average CAF content was highest 3.2% in the cultivars suitable for oolong tea in the 1st spring and the lowest 2.5% in the cultivars suitable for green tea in summer. Limited seasonal and varietal variations were noticed in the average levels of We among the three categories of tea. In addition, significant natural variation of the morphological characteristics, bud length varying from 2.5 cm to 8.7 cm, bud density from 190.3 buds · m-2to 1 730.3 buds · m-2, mature leaves biomass from 128.4 kg · hm-2to 2 888.4 kg · hm-2, and yield component traits of 100 buds(one bud with two leaves) dry weight from 3.7 g to37.7 g, tea yield/round from 444.6 kg · hm-2to 905.3 kg · hm-2, were observed. The aim of our evaluation was not only to identify the advantages of seasonal and clonal variations but also to provide a new viewpoint for their further application. Representative accessions were selected from the germplasm to promote the establishment of an inherent biochemical constituent expressing the quality of black, green, and oolong tea. The findings might

关键词： Camellia sinensis Biochemical components germplasm Natural variation morphology Yield

维普期刊数据库

在线全文

学校读者我要写书评

暂无评论

黄藤和单叶省藤改性处理工艺综合评价

西北农林科技大学学报（自然科学版） 2014年第3期42卷 93-98页

作者：徐鑫刘杏娥汪佑宏高龙芽王瑞安徽农业大学林学与园林学院安徽合肥230036 国际竹藤中心北京100102

【目的】优化黄藤和单叶省藤的改性处理工艺,以提高我国棕榈藤资源高附加值加工利用水平。【方法】以黄藤和单叶省藤为研究对象,选择改性方式、改性工艺、浸注量以及处理试剂4个因素分3水平进行L9(34)正交试验,对2种藤条改性处理前后主... 详细信息

【目的】优化黄藤和单叶省藤的改性处理工艺,以提高我国棕榈藤资源高附加值加工利用水平。【方法】以黄藤和单叶省藤为研究对象,选择改性方式、改性工艺、浸注量以及处理试剂4个因素分3水平进行L9(34)正交试验,对2种藤条改性处理前后主要物理力学性质及尺寸稳定性的变化进行测定,通过优序数法分析试验结果,建立最佳改性工艺。【结果】黄藤最佳改性方案为辐照处理、辐照剂量15kgy,浸注量50%,处理试剂为三聚氰胺树脂;单叶省藤最佳改性方案为辐照处理、辐照剂量15kgy,浸注量50%,处理试剂为脲醛树脂。按照对应最佳工艺,黄藤素材和改性材的气干密度、绝干密度、基本密度、抗弯弹性模量(mOe)、抗弯强度(mOR)、顺纹抗压弹性模量(mOeIC)、顺纹抗压强度(CS)依次为0.46和0.69g/cm3、0.43和0.65g/cm3、0.39和0.59g/cm3、1 525.46和1 944.71mPa、57.62和66.87mPa、1 198.49和1 688.70mPa、23.54和34.44mPa,单叶省藤素材和改性材的上述指标依次为0.55和0.77g/cm3、0.52和0.72g/cm3、0.47和0.65g/cm3、1 375.32和1 550.78 mPa、67.88和71.25 mPa、1 597.18和1 740.50mPa、31.59和36.74mPa。黄藤改性材的阻湿率(mee)和抗吸水率(RWA)分别为16.69%和125.10%,单叶省藤改性材的阻湿率和抗吸水率分别为23.56%和81.62%。【结论】改性材的密度、mOe、mOR、mOeIC、CS、mee和RWA等大部分物理力学性质及尺寸稳定性均有显著改善。

关键词：黄藤单叶省藤改性处理藤材材性优序数法

维普期刊数据库

统计学笔记:相对差异百分比、对称性和自然对数

在线全文

学校读者我要写书评

暂无评论

英国医学杂志中文版 2022年第12期25卷 729-731页

作者： Tim J Cole Douglas g Altman 李戈(译) 刘欣月(译) 孙凤(校) Population Policy and Practice ProgrammeGreat Ormond Street Institute of Child HealthUniversity College LondonLondon WC1N 1EHUK Centre for Statistics in medicine Nuffield Department of OrthopaedicsRheumatology and Musculoskeletal SciencesUniversity of OxfordOxford OX37LDUK 天津中医药大学健康科学与工程学院北京大学公共卫生学院流行病与卫生统计学系

对数变换具有非常实用的性质,因此在统计学中被广泛应用,但是即便是统计学家对其属性也知之甚少,而非统计学家则感觉其很不友好。对数变换两种常见形式为:以10为底的普通对数(lg)和以e作底的自然对数(ln)。以自然对数为例,解释如下:任... 详细信息

对数变换具有非常实用的性质,因此在统计学中被广泛应用,但是即便是统计学家对其属性也知之甚少,而非统计学家则感觉其很不友好。对数变换两种常见形式为:以10为底的普通对数(lg)和以e作底的自然对数(ln)。以自然对数为例,解释如下:任意两个数字a、b,其对数差ln(a)-ln(b),实际上反映的是二者比值大小。在此结果上乘以100,100xln(a)-100xln(b),即为α、b基于对数变换的相对差异百分比。

关键词：对数变换自然对数统计学家常见形式对称性百分比

两种形式添加蛋氨酸对临产荷斯坦奶牛采食量和泌乳性能的影响

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

饲料博览 2010年第2期 44-44页

作者： Ordway R S Boucher S e Whitehouse N L Schwab C g Sloan B K

试验根据胎次和预产期对18头初产荷斯坦奶牛和42头经产荷斯坦奶牛分组,并随机分配给3个日粮处理,基础日粮(负对照组),基础日粮+2-羟基-4-甲硫基丁酸异丙酯(metaSmart,为法国安东尼Adisseo公司的产品),基础日粮+瘤胃保护蛋氨酸(Smartamin... 详细信息

试验根据胎次和预产期对18头初产荷斯坦奶牛和42头经产荷斯坦奶牛分组,并随机分配给3个日粮处理,基础日粮(负对照组),基础日粮+2-羟基-4-甲硫基丁酸异丙酯(metaSmart,为法国安东尼Adisseo公司的产品),基础日粮+瘤胃保护蛋氨酸(Smartaminem,为佐治亚州阿尔法利塔Adisseo公司的产品)。试验从预产期前21d至产后140d。除了代谢蛋白质的蛋氨酸含量不同以外,日粮的原料和化学组成相似。为获得代谢蛋白质中赖氨酸与蛋氨酸3.0:1的比率,基础日粮中加入metaSmart(产前0.35%日粮干物质、产后0.54%干物质)和Smartamine m(产前0.06%日粮干物质、产后0.10%日粮干物质)。试验结果表明,母牛产前处理之间的干物质采食量(DmI,13.5kg·d-1)、体重(687kg)、体况评分(3.81),产后产奶量(42.0kg·d-1)、乳脂量(1549g·d-1)、乳脂率(3.66%)、乳真蛋白量(1192g·d-1)、乳中尿素氮含量(12.9mg·d-1·L-1)无显著差异。同饲喂对照组日粮和Smartaminem日粮的母牛比较,饲喂meta-Smart日粮母牛的产后DmI和体况评分要高,而牛奶DmI和牛奶氮、饲料氮要低。Smartaminem组(2.87%)和meta-Smart组(2.81%)的乳蛋白率高于对照组(2.72%)。处理组之间的血浆总氨基酸中蛋氨酸和蛋氨酸+胱氨酸浓度是不同的,Smarta-minem组的最高,其次是metaSmart组和对照组。试验结果表明,在提供代谢蛋氨酸方面,加入meta-Smart和Smarta-minem一样有效,但仍需要阐明代谢蛋氨酸的相对贡献。

关键词：蛋氨酸蛋氨酸类似物氨基酸奶牛

Simultaneous Repair of Para-Umbilical Hernia during Cesarean Section (CS): A Novel Approach

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Surgical Science 2018年第7期9卷 233-242页

作者： eman A. eltokhy Ibtsam Shehta Harera Loay m. gertallah Walid A. mawla Ahmed mahmoud Abdou entsar R. mahdy Ahmed embaby Department of general Surgery Faculty of Medicine Zagazig University Zagazig Egypt Department of gynecology and Obstetrics Faculty of Medicine Zagazig University Zagazig Egypt Department of Internal medicine Faculty of Medicine Zagazig University Zagazig Egypt

Background: Pregnant women that are complaining from paraumbilical hernia postpone its repair until they get birth. We hypothesized that it will be better to perform hernia repair of such type of hernia simultaneously during performing cesarean section (CS) which will help to decrease future morbidity re-operation, avoid complications and further skin incision. In this study we aimed to compare the value of performing para-umbilical hernia repair simultaneously during performing CS through the same skin incision with performing para-umbilical hernia repair simultaneously during performing CS through another infra- or supra-umbilical skin incision and performing para-umbilical hernia repair electively later on after healing of a CS skin incision in relation to clinical recovery and patient satisfaction. Patients and methods: This is a prospective cohort study, where we included 45 pregnant female patients who will give birth by CS, and we have divided them into 3 groups: the first group of patients (A) included 15 patients that undergoing paraumbilical hernia repair by pre-peritoneal mesh insertion through CS incision, the second group of patients (B) in-cluded 15 patients that undergoing paraumbilical hernia repair by infra- or supra-umbilical incision during CS incision and the third group of patients (C) included 15 patients that undergoing paraumbilical hernia repair by infra- or supra-umbilical incision later on after healing of the CS wound. We have evaluated advantages of that novel approach e.g. operation time, severity of pain, peri-partum and post-operative complications, financial cost, duration of hospital stay, clinical recovery, mesh rejection, and patient satisfaction. Results: In group A there is shorter duration of hospital stay, no new skin incision (p 0.002). Conclusions: Performing para-umbilical hernia repair by insertion of a pre-peritoneal mesh simultaneously during performing CS through the same skin incision is the best method of management o

关键词： Para-Umbilical Hernia Pre-Peritoneal mesh Insertion Pregnancy Cesarean Section Outcome

强效高选择性PPAR-α激动剂对致动脉粥样硬化性血脂紊乱或高胆固醇血症患者的影响—两项随机对照试验

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

美国医学会杂志（中文版） 2008年第2期27卷 76-86页

作者： Steven e. Nissen, mD Stephen J. Nicholls, mBBS, PhD Kathy Wolski, mPH Daniel C. Howey, mD ellen mcerlean, RN, mSN ming-Dauh Wang, PhD elisa V. gomez, mS John m. Russo, mD 靳文英(译) 顾佳(校) Department of Cardiovascular medicine Cleveland Clinic Lemer School of Medicine Cleveland Ohio eli Lilly and Company Indianapolis Ind guilford medical Associates and moses Cone Health System Greensboro. NC 不详

背景：贝特类药物是一种较弱的过氧化体增殖物激活型受体仪（peroxisome proliferators-activated receptor-α，PPAR-α）激动剂。目前尚无有关效果更强、选择性更高的相关制剂的报道。目的：研究PPAR-α激动剂LY518674的安全性和疗效... 详细信息

背景：贝特类药物是一种较弱的过氧化体增殖物激活型受体仪（peroxisome proliferators-activated receptor-α，PPAR-α）激动剂。目前尚无有关效果更强、选择性更高的相关制剂的报道。目的：研究PPAR-α激动剂LY518674的安全性和疗效。设计、地点及参试者：开展两项多中心、随机、双盲、安慰剂对照研究，其中一项针对高甘油三酯及低HDL-C血症患者（致动脉粥样硬化陛血脂紊乱），另一项针对高LDL-C患者（即高胆固醇血症）。2005年8月至2006年8月，参与血脂紊乱研究的研究人员在美国医疗中心随机入选309例患者，参与高胆固醇血症研究的研究人员入选304例患者。干预：在血脂紊乱研究中，患者服用安慰剂、非诺贝特（200mg）或LY518674（10μg、25μg、50μg或100μg），共12周。在高胆固醇血症研究中，患者首先服用安慰剂或阿托伐他汀（10mg或40mg）4周，然后服用安慰剂或LY518674（10μg或50μg）12周。主要观测指标：血脂紊乱研究的观测指标为HDL-C和甘油三酯变化的百分比，高胆固醇血症研究的观测指标为LDL-C变化的百分比。结果：血脂紊乱研究显示，LY518674（25μg）和非诺贝特分别使HDL—C水平增加5．9mg／dL和5．5mg／dL（15．8％和14．4％）（与安慰剂相比P值均≤0．001，组间比较P：0．79）。更高剂量的LY518674对HDL．C水平的影响不大。LY518674可使甘油三酯水平降低97．3～114．5rag／de（34．9％～41．7％），与非诺贝特效果相似。LY518674可使LDL—C水平呈剂量依赖性升高，100μg LY518674可使LDL—C升高20．4mg／dL（19．5％），而非诺贝特仅使LDL-C升高0．3mg／dL（2．3％）。非诺贝特和LY518674（50μg和100μg）均可增加血清肌酐值（与安慰剂相比P≤0．001），分别有38％和37．3％的患者肌酐值超出正常范围。非诺贝特还可增加磷酸肌酸激酶水平（与安慰剂相比P=0．004），LY518674则无此反应。高胆固醇血症研究显示，LY518674（10μg或50μg）可使LDL—C降低21．4～26．0mg／dL（13．2％～15．8％），使甘油三酯降低约37％，使HDL-C升高6．3～6．7mg／dL（12．5％～15．0％）。当与阿托伐他汀合用时，LY518674可使HDL．C变化-0．7～6．2mg／dL（-0．6％～11．9％），使甘油三酯显著降低，但对LDL—C无明显的进一步降低作用。结论：在血脂紊乱患者中，LY518674和非诺贝特可降低甘油三酯水平，升高HDL-C水平，但同时也增加血清肌酐水平。与非诺贝特不同，LY518674还可升高LDL-C水平。在高胆固醇血症患者中，LY518674可降低甘油三酯水平，升高HDL-C水平，但与阿托伐他汀合用时并不能进一步降低LDL—C水平。非诺贝特和LY518674的安全陛均需进一步观察。

关键词：高胆固醇血症随机对照试验 PPAR-α 血脂紊乱动脉粥样硬化性激动剂高选择性过氧化体增殖物激活型受体