22 research outputs found

    Progress in Chiral Sensors

    Get PDF
    手性工程的崛起对简单、经济、快速、实时、在线的手性检测技术提出了挑战。手性传感器是一个重要的发展趋势。本文综述了近年来在手性电化学传感器、基于石英晶体微天平的手性质量化学传感器及手性光学传感器方面的研究进展,重点介绍了各种传感器的制备及其在手性检测中的应用,并展望了该领域的发展前景。The development of chiral engineering requires chiral analytical technologies with simple handling,low cost,high speed,real time and on-line operation.Chiral sensor system represents a major branch of future research.In this paper,the progress in chiral electrochemical sensor,chiral mass chemical sensor based on quartz crystal microbalance and chiral optical sensor is reviewed.The preparations and applications of these chiral sensors are introduced.The prospects of this field are also put forward.福建省自然科学基金项目(No.C0540024);; 福建省教育厅课题(No.JA05301)资

    Infection Status and Influencing Factors of Human Papillomavirus in Patients with Condylomata Acuminata

    Get PDF
    目的了解我国内地尖锐湿疣(CA)患者的人乳头瘤病毒(HPV)感染状况,并探讨其影响因素。方法系统检索Pub Med、Science Direct Online、中国知网、万方数据知识服务平台、维普网中关于我国内地CA患者HPV检测的文献,检索时间均为1990年1月—2013年12月。根据样本量对各文献HPV感染率进行加权合并,计算CA患者的HPV及各基因型合并感染率,并分析不同研究年份、研究地区CA患者的HPV合并感染率,采用多因素Logistic回归分析探讨CA患者感染/检出HPV的影响因素。结果共纳入文献67篇,累计CA患者10 757例,感染HPV 9 328例(86.7%)。CA患者的HPV合并感染率为95.7%〔95%CI(95.2%,96.2%)〕,其中合并感染率较高的前3种基因型为HPV6/11〔81.2%,95%CI(77.1%,85.2%)〕、HPV6〔43.8%,95%CI(35.2%,52.5%)〕、HPV11〔38.3%,95%CI(32.8%,43.8%)〕。1990—2003、2004—2013年CA患者的HPV合并感染率分别为96.6%〔95%CI(95.8%,97.5%)〕、94.6%〔95%CI(94.0%,95.3%)〕;东、中、西部患者的HPV合并感染率分别为95.1%〔95%CI(94.4%,95.7%)〕、91.7%〔95%CI(89.3%,94.1%)〕、96.5%〔95%CI(95.4%,97.6%)〕。多因素Logistic回归分析结果显示,研究年份、研究地区、标本类型、诊断方法是CA患者感染/检出HPV的影响因素(P〈0.05)。对不同基因型进行分析,结果显示,研究年份、研究地区、标本类型、诊断方法是CA患者感染/检出HPV6的影响因素,研究年份、研究地区为西部、标本类型、诊断方法是CA患者感染/检出HPV11的影响因素,研究地区为中部、标本类型是CA患者感染/检出HPV16的影响因素,研究地区、标本类型、诊断方法是CA患者感染/检出HPV18的影响因素(P〈0.05)。结论我国内地CA患者的HPV感染以HPV6、HPV11基因型为主,感染率近10年来有所下降,东部地区感染率较高。病理检查确诊、采用剥落细胞进行DNA检测,可以提高CA患者的HPV检出率。Objective To study the infection status of human papillomavirus(HPV) in patients with condylomata acuminata(CA) in mainland China and explore its influencing factors. Methods The literatures on HPV detection of CA patients in mainland China published between January 1990 and December 2013 were systematically retrieved from Pub Med,Science Direct Online, China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, and the VIP database. According to the sample size,HPV infection rates of each literature were weighted and combined and the infection rates of HPV and the combined infection rate of each genotype of CA patients were calculated,and the combined infection rate of HPV of CA patients in different years and areas of study was analyzed. Multivariate Logistic regression analysis was used to investigate the influencing factors of CA patients infected / detected with HPV. Results A total of 67 literatures were included in the study. The number of CA patients accumulated to 10 757,and 9 328 cases(86. 7%) infected with HPV. The combined infection rate of HPV in patients with CA was 95. 7% 〔95% CI(95. 2%,96. 2%) 〕,and the top three genotypes with high infection rate were HPV6 /11 〔81. 2%,95% CI(77. 1%,85. 2%) 〕, HPV6 〔43. 8%,95% CI(35. 2%,52. 5%) 〕, HPV11〔38. 3%,95% CI(32. 8%,43. 8%) 〕. The combined infection rate of HPV in patients with CA between 1990 and 2003 and between 2004 and 2013 was 96. 6% 〔95% CI(95. 8%,97. 5%) 〕and 94. 6% 〔95% CI(94. 0%,95. 3%) 〕respectively;the combined infection rate of HPV of patients in eastern, middle and western areas was 95. 1% 〔95% CI(94. 4%,95. 7%) 〕,91. 7% 〔95% CI(89. 3%,94. 1%) 〕,and 96. 5% 〔95% CI(95. 4%,97. 6%) 〕respectively. Multivariate Logistic regression analysis showed that the year of study,areas of study,type of specimen and methods of diagnosis significantly influenced the infection and detection of HPV in CA patients(P 0. 05). After analyzing different genoty福建省自然科学基金青年项目(2014J05097

    金属固溶体热膨胀系数的CALPHAD计算模型

    Get PDF
    基于计算相图方法(CALPHAD方法),借鉴经典热容模型,通过增加额外的磁性项参数,构建了包含铁磁-顺磁转变的金属固溶体热膨胀系数的CALPHAD计算模型。结合Ni-Fe二元合金的实验结果,采用Levenberg-Marquardt法对模型参数进行了评估,优化得到了300~1200 K范围内Ni-Fe二元金属固溶体热膨胀系数的相互作用参数。采用得到的模型参数,对Ni-Fe二元金属固溶体的热膨胀系数进行了计算,计算结果准确地描述了Ni-Fe二元金属固溶体在居里温度附近的尖锐峰。随着Fe含量的增加,居里温度处的峰值减小,热膨胀曲线由峰状变成谷状,与实验值吻合。该计算模型可以准确计算任意Fe含量<50%(质量分数)的Ni-Fe二元金属固溶体的热膨胀系数。国家重点研发计划项目(2017YFB0701603,2016YFB0701401)福建省自然科学基金项目(2016J01256)国家自然科学基金青年基金项目(51601161

    Chlorofullerenes featuring triple sequentially fused pentagons

    Get PDF
    通讯作者地址: Tan,YZ(通讯作者),Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China 电子邮件地址: [email protected], [email protected] triple sequentially fused pentagons (TSFP) motif is one of the basic subunits that could be used for constructing fullerenes, but it violates the isolated pentagon rule (IPR) and has not been found in carbon cages to date. The properties of TSFP-incorporating fullerenes are thus poorly explored both theoretically and experimentally. Reported herein are four chlorinated derivatives of three different fullerene cages, all with the TSFP motif. X-ray crystallographic analyses indicate that the molecular strain inherent to the pentagon adjacency of a TSFP is significantly relieved upon exohedral chlorination, leaving one of the four pentagon fusion sites unsaturated and rendering the present derivatives chiral. This unique reactivity, in stark contrast to that of previously reported non-IPR fullerenes containing double fused pentagons or triple directly fused pentagons, can be rationalized by density functional theory calculations, and are expected to stimulate further studies of these new members of the fullerene family, both theoretically and experimentally.NNSF of China 20525103,20531050,20721001,20423002 20673088 973 Program 2007CB81530

    基于评价指标为潜变量背景下的纸坊沟流域水土保持 技术评估

    No full text
    基于生态技术属性、应用、实施效果以及其特征表现为潜变量的现实,以潜变量为背景,构建了两种情境下的指标体系,在 纸坊沟流域对两种情境下的指标体系进行验证,两种情境下的评估结果与均现实相符。水土保持技术选择、应用过程以及技术 体系之间的互动关系直接涉及到的是潜变量,为了精确揭示水土保持技术的本质、明确纸坊沟流域水土保持技术应用过程及水 土保持技术体系,基于课题&ldquo;生态技术评价方法、指标与评价模型开发&rdquo;的相关研究成果以及 2018 年 5 月农户调研资料,构建了 包括技术成熟度、技术应用难度、技术相宜性、技术效益以及技术推广潜力在内的 5 个一级指标、技术完整性等在内的 14 个二 级指标的水土保持技术评价指标体系,并对各指标进行解释,得到评判标准。采取一二级指标相互印证的方法对安塞县纸坊沟 流域水土保持技术进行评估,结果表明: 纸坊沟流域 3 个阶段水土保持技术综合得分分别为: 0.5399( 0.5191) ,0.6724( 0.6628) , 0.7866( 0.7748) ( 括号内为基于二级指标的测算结果) 。流域内水土保持技术及其应用综合效果不断提升,动因为: 水土保持技 术体系不断优化,水土保持技术选择与应用的要素的耦合度不断提升,并与农户理念趋近。</div

    水土保持技术对农业产业-资源系统的耦合路径分析

    No full text
    水土保持技术通过对农业产业-资源系统的作用过程影响系统的耦合效果,这一过程及效果成为农户选择水土保持技术 的关键点。为此,运用结构方程模型,以典型流域&mdash;县南沟流域为对象,通过对 2017 年 130 户农户调研资料的分析,揭示其作 用过程和耦合路径,结果表明: 水土保持技术与生态环境、农业资源、农业产业形成了一个新的耦合系统,水土保持技术对生态 环境的改良和农业资源量的增加具有促进作用,对农业产业的发展具有抑制作用。但其( 现阶段) 作用强度较弱, ( 水土保持技 术对三者的路径系数分别为 0.13、0.08、-0.02) ; 这是由于县南沟流域基本完成了规模化治理,故水土保持技术对农业产业-资源 系统的影响的弱强度是基于水土流失治理及治理措施有效发挥基础之上的弱强度,同时隐含了现有的水土保持技术体系已不 能完全满足新时代背景下生态文明建设与经济发展的需求,需要围绕水土保持内涵经营过程,以生态功能的提升为主线,筛选、 集成、研发水土保持技术,形成可适化水土保持技术体系。</div

    长期施肥对大豆根际微生物量碳、氮的影响

    No full text
    通过对盆栽培养模拟试验研究长期施肥对种植大豆的土壤、裸土和根际微生物量碳、氮的影响。设置化肥+有机肥(NPKOM),单施化肥(NPK),不施肥(CK)3个施肥处理。结果表明:施肥对土壤、裸土及根际中微生物量碳、氮含量的影响趋势相同,为NPKOM>NPK>CK。在土壤中,和CK处理相比较,NPK处理微生物量碳、氮的含量高出了124%和100%,NPKOM处理的微生物量碳、氮的含量增加了232%和197%。在裸土中,和CK处理相比较,NPK处理微生物量碳、氮的含量增加了116%和90%,NPKOM处理的微生物量碳、氮的含量增加了313%和240%。在根际中,和CK相比较,NPK处理的微生物量碳、氮的含量增加了127%和105%,NPKOM的微生物量碳、氮的含量增加了198%和174%,说明化肥和有机肥配合施用会提高微生物的数

    A Fault Detection Method for Control Valve Based on Noise Analysis

    No full text
    针对调节阀的在线故障检测问题,文中提出了一种基于噪声分析的故障检测方法。该方法首先利用小波分解技术提取过程信号的噪声;然后,通过数字滤波减少干扰信号;最后,从统计角度出发,计算过程噪声的统计数字特征(自相关函数)来检测故障是否发生。仿真结果表明:该方法可以检测出气动调节阀的阀门堵塞故障,同时验证了该方法的可行性与有效性
    corecore