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Chinese Journal of Polymer Science 2023年第8期41卷 1287-1297,I0010页

作者： zhou-xian li Yi-Ran Kong xiang-Fei Chen Ya-Jiang Huang Ya-Dong Lv Guang-xian li College of polymer science and engineering State key laboratory of polymer materials engineering of ChinaSichuan UniversityChengdu 610065China

The aging of natural rubber(NR)at high temperatures will seriously affect its service lifetime in many key *** the present work,the changes in microstructure and mechanical properties of semi-efficient vulcanized NR/carbon black(CB)vulcanizates during thermooxidative aging at high temperatures(150-200℃)and a moderate temperature(95℃)were *** high temperatures,a two-stage aging behavior,which was characteristic of a first rapid decline and then a continuous rise in the crosslinking density(ve),was identified and was found to be closely related to the depletion behavior of *** surface cracking behavior observed in the second stage of high-temperature aging was discussed in terms of the grafting reaction of macromolecular radicals on CB particles and thermal *** contrast,the aging of NR at moderate temperatures was much mild,which featured a continuous increase in ve and an oxidation mechanism dominated by peroxy radicals attacking double *** general,the mechanical properties of NR vulcanizates during high-temperature aging depended on the competition effects of structural evolution in the crosslinked network and oxidation-induced chain scission.

关键词： Natural rubber nanocomposites High-temperature Thermo-oxidative aging

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Antitumor activity of nervosine Ⅶ,and the crosstalk between apoptosis and autophagy in HCT116 human colorectal cancer cells

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Chinese Journal of Natural Medicines 2020年第2期18卷 81-89页

作者： HUANG Shuai ZHAO Shuang-Mei SHAN lian-Hai zhou xian-li School of life Science and Engineering Southwest Jiaotong UniversityChengdu 610031China

Nervosine Ⅶ is one of the known saturated pyrrolizidine alkaloids isolated from the plant of liparis *** is first study to investigate the antitumor activity of nervosine Ⅶ in vitro,and the results indicated that nervosine Ⅶ induced autophagy and apoptosis in HCT116 human colorectal cancer *** studies showed that nervosine Ⅶ-induced apoptosis was associated with the intrinsic pathway by the activation of caspase-9,-3 *** induced by nervosine Ⅶ was characteristic with the regulation of autophagic markers including the increase of LC3-Ⅱ and beclin 1 proteins,and the decrease of p62 *** Ⅶ simultaneously induced autophagy and apoptosis by activated MAPKs signaling pathway including JNK,ERK1/2 and p38,suppressing the p53 signaling pathway.

关键词： liparis nervosa Pyrrolizidine alkaloids NervosineⅦ Autophagy Apoptosis HCT116 cells

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Effect of dissolved organic matter on the toxicity of chlorotoluron to Triticum aestivum

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Journal of Environmental Sciences 2006年第1期18卷 101-108页

作者： SONG Ning-hui YANG Zhi-min zhou li-xian WU Xin YANG Hong College of Science Nanjing Agricultural University Nanjing 210095 China College of life Science Nanjing Agricultural University Nanjing 210095 China College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China

Response of two wheat cultivars （Triticum aestivum cv. YM 158 and NM 9） to the herbicide chlorotoluron and the effect of two forms of dissolved organic matter on the chlorotoluron toxicity to the plants were characterized. Treatment with chlorotoluron at 10-50 μg/ml inhibited the seed germination and a dose-response was observed. The inhibition of seed germination was correlated to the depression of a-amylase activities. To identify whether chlorotoluron induced oxidative damage to wheat plants, the malondlaldehyde （MDA） content and electrolyte leakage were measured. Results showed that both MDA content and electrolyte leakage in the chlorotoluron-treated roots significantly increased. Activities of several key enzymes were measured that operate in citric acid cycle and carbohydrate metabolic pathway. Inhibited activities of citrate synthase and NADP-isocitrate dehydrogenase were observed in the chlorotoluron-treated roots as compared to control plants. We also examined malate dehydrogenase and phosphoenolpyruvate carboxylase in wheat roots exposed to 30 μg/ml chlorotoluron, liowever, none of the enzymes showed significant changes in activities. Application of 160 μg/ml dissolved organic matter （DOM） extracted from non-treated sludge（NTS） and heat-expanded sludge （liES） in the medium with 30 μg/ml chlorotoluron induced an additive inhibition of seed germination and plant growth. The inhibition of growth due to the DOM treatment was associated with the depression of activities of a-amylase, citrate synthase and NADP-isocitrate dehydrogenase, as well as the increase in malondlaldehyde content and electrolyte leakage. These results suggested that the presence of DOM might enhance the uptake and accumulation of chlorotoluron, and thus resulted in greater toxicity in wheat plants. The two forms of DOM exhibited differences in regulation of chlorotoluron toxicity to the wheat plants. Treatments with DOM-NTS induced greater toxicity to plants as compared to those with DOM-

关键词： dissolved organic matter chlorotoluron Triticum aestivum toxicity

基于SSR标记的青海蚕豆品种亲缘关系分析与指纹图谱构建

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作物学报 2025年第1期51卷 79-90页

作者：郑栋周仙莉滕长才侯万伟张红岩刘玉皎青海大学青海西宁810016 青海省农林科学院青海西宁810016 青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016 国家农作物种质资源复份库青海西宁810016

为明确青海蚕豆育成品种、高代品系和骨干亲本的群体结构与亲缘关系,本研究利用46对多态性和稳定性好、重复性高的SSR引物对36个青海蚕豆主栽品种(品系)进行群体遗传学分析并构建了指纹图谱。结果表明,通过毛细管电泳检测,在46对引物中... 详细信息

为明确青海蚕豆育成品种、高代品系和骨干亲本的群体结构与亲缘关系,本研究利用46对多态性和稳定性好、重复性高的SSR引物对36个青海蚕豆主栽品种(品系)进行群体遗传学分析并构建了指纹图谱。结果表明,通过毛细管电泳检测,在46对引物中检测到262个等位位点,各引物检测的多态性等位位点数(Na)为2~15,平均等位位点数为5.696个,平均每个位点检测到的有效等位基因数为2.988个,范围为1.180~9.257;Shannon指数的变化范围为0.287~2.444,均值为1.210;多态性信息含量(polymorphism information content, PIC)值变化范围为0.141~0.883,均值为0.553,揭示了青海蚕豆品种丰富的遗传多样性。系统聚类将36份材料划分为4个亚群,第Ⅰ、Ⅱ、Ⅲ、Ⅳ亚群分别包括24、4、7、1份材料;群体结构与主坐标分析将材料划分为2个亚群,亚群Ⅰ和亚群Ⅱ分别包括17和19份材料,与聚类分类结果有一定程度的交叉重合,厘清了青海蚕豆主栽品种的群体遗传结构与亲缘关系。在此基础上,筛选出4对核心引物,构建了36份材料的指纹图谱,并将相关信息储存在二维码中。青海蚕豆主栽品种指纹图谱的构建不仅为青海蚕豆品种鉴定提供了有效工具,也为今后青海蚕豆品种亲本选配和新品种权保护提供了技术支撑。

关键词：蚕豆青海主栽品种 SSR标记亲缘关系指纹图谱

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磷钒钼黄光度法测定钒磷铁矿中磷

冶金分析 2018年第9期38卷 75-80页

作者：周礼仙攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室

采用无水碳酸钠和硼酸混合熔剂分解样品,在硝酸介质中,高锰酸钾将其他形式的磷酸根氧化为正磷酸根,以亚硝酸钠还原过量的高锰酸钾。在约0.80mol/L的酸度下,磷与钼酸铵、钒酸铵反应生成可溶性的磷钒钼黄络合物,实现了磷钒钼黄分光光度法... 详细信息

采用无水碳酸钠和硼酸混合熔剂分解样品,在硝酸介质中,高锰酸钾将其他形式的磷酸根氧化为正磷酸根,以亚硝酸钠还原过量的高锰酸钾。在约0.80mol/L的酸度下,磷与钼酸铵、钒酸铵反应生成可溶性的磷钒钼黄络合物,实现了磷钒钼黄分光光度法对样品中磷的测定。在选定的实验条件下,显色液中磷的质量在0.023~0.278mg范围内符合比尔定律,校准曲线的相关系数为0.999 8。方法检出限为0.20%(质量分数),测定下限为0.60%(质量分数)。考察了钒磷铁矿样品中钒、铬及其他共存元素对测定的干扰,结果表明这些共存元素的干扰均可忽略。选取6件钒磷铁矿样品,分别采用实验方法与国标方法 GB/T 1871.1—1995(包括磷钼酸喹啉重量法和滴定法)作对照分析,二者测定结果基本一致。采用实验方法对钒磷铁矿样品进行8次平行测定,相对标准偏差(RSD,n=8)小于4%,在样品中加入磷标准溶液进行加标回收试验,回收率在98%~101%之间。

关键词：钒磷铁矿磷分光光度法

An Approach to Hierarchy Distributed Cooperative Decision-Making System Based on Blackboard

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微计算机信息 2005年第26期 200-202+87页

作者： Lu,Qiuqin Huang,Guangqiu zhou,Jing Mei,li(xian University of Architecture & Technology, Xi- an 710055, China)

This paper presents the concept of a new DCDSS, which is called the blackboard oriented distributed cooperative decision- making system (BODCDSS). The hierarchy architecture of the whole system according to the logical function is de- signed; the techniques of modules implementation of user, agent and data warehouse are given; the distributed group cooperation models and the distributed cooperation algorithms are described; some feasible methods of venture and uncertain decision- making problems are put forward.

关键词： Distributed Cooperative Decision System (DCDSS) Distributed Cooperation Blackboard System

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硫氰酸盐分光光度法测定镍基合金中钨

冶金分析 2017年第8期37卷 78-82页

作者：周礼仙攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室

应用硫氰酸盐分光光度法测定镍基合金试样中钨时,存在镍基合金较难溶解的问题,同时样品中较高含量的镍会干扰钨的测定。实验采用硝酸-氢氟酸混合酸溶解试样,通过加入氢氧化钠使其与基体镍反应生成氢氧化镍沉淀的方法实现了镍与钨的分离... 详细信息

应用硫氰酸盐分光光度法测定镍基合金试样中钨时,存在镍基合金较难溶解的问题,同时样品中较高含量的镍会干扰钨的测定。实验采用硝酸-氢氟酸混合酸溶解试样,通过加入氢氧化钠使其与基体镍反应生成氢氧化镍沉淀的方法实现了镍与钨的分离,然后用氯化亚锡作还原剂,在盐酸介质中,将钨被还原为钨(Ⅴ)与硫氰酸盐形成黄色配合物,建立了硫氰酸盐分光光度法测定镍基合金中钨的方法。实验表明,显色液中钨的质量浓度在0.096~19.24μg/mL范围内符合比尔定律,相关系数R~2=0.999 6。方法的检出限为0.025%,测定下限为0.084%。将实验方法用于测定两个镍基合金样品中钨,结果的相对标准偏差(RSD,n=6)小于0.50%。按照实验方法测定6个镍基合金样品中钨,结果与电感耦合等离子体原子发射光谱法(ICP-AES)测定结果相一致。

关键词：镍基合金钨硫氰酸盐分光光度法

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铋磷钼蓝分光光度法测定钛白粉中磷

冶金分析 2016年第9期36卷 57-61页

作者：周礼仙攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室

钛白粉中大量存在的钛在分解时易水解形成较细的沉淀,即使反复过滤,滤液中都残留有少量细小沉淀颗粒,故而会影响光度法对磷的测定。针对这一问题,实验采用无水碳酸钠和硼酸混合熔剂熔融钛白粉试样,再加入硫酸中低温溶解熔融样,然后在硫... 详细信息

钛白粉中大量存在的钛在分解时易水解形成较细的沉淀,即使反复过滤,滤液中都残留有少量细小沉淀颗粒,故而会影响光度法对磷的测定。针对这一问题,实验采用无水碳酸钠和硼酸混合熔剂熔融钛白粉试样,再加入硫酸中低温溶解熔融样,然后在硫酸介质中,加入高锰酸钾将磷氧化为正磷酸根的形式存在于溶液中,加入氢氧化钠与基体钛反应生成三钛酸钠沉淀,过滤,实现了钛与磷的分离,从而建立了铋磷钼蓝光度法测定钛白粉中磷的测定方法。在优化的实验条件下,磷质量浓度在0.009~0.382μg/mL范围内与其吸光度符合比尔定律,校准曲线的相关系数为0.999 9。采用实验方法对钛白粉样品进行8次平行测定,结果的相对标准偏差(RSD,n=8)小于4.0%,回收率在98%~103%之间。采用微波消解-电感耦合等离子体质谱法(ICP-MS)进行方法对照试验,结果表明两种方法的测定结果基本一致。

关键词：钛白粉磷铋磷钼蓝分光光度法

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硫酸亚铁铵滴定法测定钛铝钒合金中钒

冶金分析 2018年第6期38卷 70-74页

作者：周礼仙攀钢集团研究院有限公司钒钛资源综合利用国家重点实验室

应用硫酸亚铁铵滴定法测定钛铝钒合金中钒时,存在试样较难溶解且试样中较高含量钛易水解干扰终点颜色判断的问题。实验采用硝酸-氢氟酸-硫酸体系溶解试样,通过加入氢氧化钠使其与基体钛发生反应生成三钛酸钠沉淀的方法实现了钛与钒的分... 详细信息

应用硫酸亚铁铵滴定法测定钛铝钒合金中钒时,存在试样较难溶解且试样中较高含量钛易水解干扰终点颜色判断的问题。实验采用硝酸-氢氟酸-硫酸体系溶解试样,通过加入氢氧化钠使其与基体钛发生反应生成三钛酸钠沉淀的方法实现了钛与钒的分离,于硫-磷混酸介质中,用高锰酸钾将滤液中的钒全部氧化为五价钒,以亚硝酸钠还原过量的高锰酸钾,再用尿素分解多余的亚硝酸钠,以N-苯代邻氨基苯甲酸为指示剂,用硫酸亚铁铵标准溶液滴定钒,建立了硫酸亚铁铵滴定法测定钛铝钒合金中钒的方法。共存元素干扰试验说明试样中的共存元素不干扰测定。将实验方法应用于测定两个钛铝钒合金试样中的钒（质量分数在3%;%之间）,结果的相对标准偏差（RSD,n=6）为0.20%和0.25%。按照实验方法测定6个钛铝钒合金试样中钒,结果与火焰原子吸收光谱法（FAAS）测定值相一致。

关键词：钛铝钒合金钒硫酸亚铁铵滴定法

Self-expanding metallic stents drainage for acute proximal colon obstruction

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World Journal of Gastroenterology 2011年第28期17卷 3342-3346页

作者： li-Qin Yao Yun-Shi Zhong Mei-Dong Xu Jian-Min Xu Ping-Hong zhou xian-li Cai Department of Endoscopic Center Zhongshan Hospital Fudan University Medical Center Shanghai200032 China

AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative ***: Eighty-one colon (proximal to spleen flex) carcinoma patients (47 males and 34 females,aged 18-94 years,mean = 66.2 years) treated between September 2004 and June 2010 for acute colon obstruction were enrolled to this study,and their clinical and radiological features were *** a cleaning enema was administered,urgent colonoscopy was ***,endoscopic decompression using SEMS placement was ***: Endoscopic decompression using SEMS placement was technically successful in 78 (96.3%) of 81 *** patients’ symptoms could not be relieved after SEMS placement and emergent operation was performed 1 d *** site of obstruction was transverse colon in 18 patients,the hepatic flex in 42,and the ascending colon in *** adequate cleansing of the colon,patients’ abdominal girth was decreased from 88 ± 3 cm before drainage to 72 ± 6 cm 7 d later,and one-stage surgery after 8 ± 1 d (range,7-10 d) was *** anastomotic leakage or postoperative stenosis occurred after ***: SEMS placement is effective and safe in the management of acute proximal colon obstruction due to colon carcinoma,and is considered as a bridged method before curative surgery.

关键词： Endoscope Proximal colon cancer Obstruction Self-expanding metallic stents Drainage