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表n为连续奇偶数的和之方法数
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作者 何钟 《中学数学研究(华南师范大学)(上半月)》 2003年第8期38-38,共1页
<正> 设自然数 n 的标准分解式为n=2~αP_1~α 1 P_2~α 2…p_k~α k,(1)其中 k,α为非负整数,p_i(1≤i≤k)为互异奇素数,α_i(1≤i≤k)为正整数.文[1]获得表 n 为连续自然数的和之方法数为f(n)={(α_1+1)(α_2+1)…(α_k+1),k≥1... <正> 设自然数 n 的标准分解式为n=2~αP_1~α 1 P_2~α 2…p_k~α k,(1)其中 k,α为非负整数,p_i(1≤i≤k)为互异奇素数,α_i(1≤i≤k)为正整数.文[1]获得表 n 为连续自然数的和之方法数为f(n)={(α_1+1)(α_2+1)…(α_k+1),k≥1,1,k=0. (2)(上面的表达式略有改进,原文忽略了 k=0的情形.)本文推广此问题,得到如下结果:定理:设 n 的标准分解式如(1)式。 展开更多
关键词 表n 连续奇偶数 方法数 高中 数学
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两种量表对NICU新生儿压力性损伤形成的预测效果 被引量:1
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作者 吕俊英 吴玉洁 +2 位作者 夏芳琴 阮淑琴 鲁萍 《温州医科大学学报》 2021年第9期759-762,共4页
目的:比较新生儿皮肤风险评估量表(NSRAS)与新生儿/婴儿Braden Q量表(N/I Braden-Q量表)对NICU新生儿压力性损伤(PI)形成的预测效果。方法:采用方便抽样法,选取温州医科大学附属第二医院育英儿童医院NICU科室106例患儿作为研究对象,每... 目的:比较新生儿皮肤风险评估量表(NSRAS)与新生儿/婴儿Braden Q量表(N/I Braden-Q量表)对NICU新生儿压力性损伤(PI)形成的预测效果。方法:采用方便抽样法,选取温州医科大学附属第二医院育英儿童医院NICU科室106例患儿作为研究对象,每天对患儿进行量表评分及皮肤检查,采用自制调查表进行资料收集,以患儿发生PI作为结局终点。结果:13例(12.3%)患儿发生PI,分布部位包括鼻部(8例)、后枕部(3例)、下唇(1例)及骶尾部(1例)。NSRAS入院当天评分、PI发生前24 h/住院中期评分、最高评分的Cronbach’sα系数为0.539、0.557、0.579,N/I Braden-Q量表三次评分的Cronbach’sα系数为0.559、0.568、0.679;NSRAS的ROC曲线下面积为0.539~0.737,N/I Braden-Q量表的ROC曲线下面积为0.725~0.875。结论:N/I Braden-Q量表预测效度高于NSRAS,更适用于预测NICU新生儿PI形成。 展开更多
关键词 压力性损伤 重症监护病房 新生儿 新生儿皮肤风险评估量 n/I Braden Q量
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应用软件复杂条件处理的详细设计方法——N+2表法
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作者 王咏 《温州大学学报(自然科学版)》 2013年第4期32-39,共8页
对于应用软件中复杂条件处理或加工的详细设计,针对传统的过程设计工具存在的问题,依据集合论提出了N+2表方法.该方法通过构造特定结构的二维表——N+2表来快速获取处理逻辑,用行扫描算法替代嵌套的多层条件判断以实现处理逻辑,更为重... 对于应用软件中复杂条件处理或加工的详细设计,针对传统的过程设计工具存在的问题,依据集合论提出了N+2表方法.该方法通过构造特定结构的二维表——N+2表来快速获取处理逻辑,用行扫描算法替代嵌套的多层条件判断以实现处理逻辑,更为重要的是该方法使得条件组合、动作以及二者之间的映射独立于程序和算法,通过元组增、删、改操作就可以实现处理逻辑的动态变化.多个信息系统的开发实践表明,该方法比传统方法具有明显的优势. 展开更多
关键词 复杂条件处理 详细设计方法 n+2
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EPQ中N量表高分者的笔迹特征 被引量:1
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作者 陈连森 姜其和 《中国心理卫生杂志》 CSSCI CSCD 北大核心 1996年第5期210-210,共1页
EPQ中N量表高分者的笔迹特征山东省临沂教育学院教育系陈连森,姜其和汉字笔迹有着丰富的表现力和明显的个人特征,我国古代有“字如其人”的说法。笔者在使用艾森克个性问卷(EPQ)的过程中发现,汉字笔迹迹在用笔、点划、结字... EPQ中N量表高分者的笔迹特征山东省临沂教育学院教育系陈连森,姜其和汉字笔迹有着丰富的表现力和明显的个人特征,我国古代有“字如其人”的说法。笔者在使用艾森克个性问卷(EPQ)的过程中发现,汉字笔迹迹在用笔、点划、结字、布白特征与N量表高分存在着对应的... 展开更多
关键词 艾森克个性问卷 n 笔迹
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中文版Braden-Q量表和N/I Braden-Q量表在NICU新生儿压力性损伤风险评估中的应用对比研究 被引量:9
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作者 周毅先 姚香莉 +4 位作者 程功梅 王文娟 王艳娇 马姣媚 任姣阳 《护士进修杂志》 2020年第12期1093-1096,共4页
目的比较Braden-Q量表和N/I Braden-Q量表在NICU新生儿压力性损伤风险评估中的预测效能。方法采用便利抽样的方法,选取于2019年8月-2020年2月在空军军医大学第一附属医院、第二附属医院、西北妇女儿童医院NICU住院治疗的512例新生儿作... 目的比较Braden-Q量表和N/I Braden-Q量表在NICU新生儿压力性损伤风险评估中的预测效能。方法采用便利抽样的方法,选取于2019年8月-2020年2月在空军军医大学第一附属医院、第二附属医院、西北妇女儿童医院NICU住院治疗的512例新生儿作为研究对象,采用Braden-Q量表和N/I Braden-Q量表对其进行压力性损伤风险评估。结果(1)共有31例(6.05%)新生儿发生压力性损伤,发生部位多为鼻部(20例,64.52%),分期均为Ⅰ期。(2)Braden-Q量表中,发生与未发生压力性损伤组总分分别为(14.90±4.89)分和(18.67±5.53)分(t=3.703,P<0.001);N/I Braden-Q量表中,发生/未发生压力性损伤组总分分别为(15.24±3.90)分和(23.08±5.25)分(t=8.167,P<0.001)。(3)Braden-Q量表ROC曲线下面积为0.776(P<0.001),当总分为18.5分时,灵敏度、特异度和约登指数分别为0.742、0.630、0.372,预测价值最大;N/I Braden-Q量表ROC曲线下面积为0.879(P<0.001),当总分为20.5分时,灵敏度、特异度和约登指数分别为0.932、0.800、0.732,预测价值最大。结论NICU新生儿压力性损伤发生率处于较低水平。Braden-Q量表和N/I Braden-Q量表总分均可提示NICU新生儿压力性损伤发生风险,两量表的预测界值分别为18.5分和20.5分时,压力性损伤风险预测效能最佳。N/I Braden-Q量表对NICU新生儿压力性损伤的预测效能高于Braden-Q量表。 展开更多
关键词 压力性损伤 新生儿 重症监护病房 Braden-Q量 n/I Braden-Q量
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翅果油树(Elaeagnus mollis)群落的种间分离 被引量:11
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作者 张殷波 张峰 《生态学报》 CAS CSCD 北大核心 2006年第3期737-742,共6页
在野外对山西翅果油树群落31个样方内所有基径≥1cm的灌木绘制空间分布图,应用最近邻体法判定每个个体的最近邻体植株,然后采用N×N最近邻体列联表及其截表(2×2最近邻体列联表)的方法,研究翅果油树群落所有灌木的种间分离规律... 在野外对山西翅果油树群落31个样方内所有基径≥1cm的灌木绘制空间分布图,应用最近邻体法判定每个个体的最近邻体植株,然后采用N×N最近邻体列联表及其截表(2×2最近邻体列联表)的方法,研究翅果油树群落所有灌木的种间分离规律。结果表明:该群落中随机毗邻种对占绝大多数(80.94%),正分离种对较少(18.78%),负分离种对极少(0.28%)。呈负分离的极少数种对是一些个体较小的小灌木,它们多为群落的伴生种,具有相近的生境需求,较激烈的种间竞争可能导致它们随机或均匀分布,因此这些种对表现出负分离;较大的个体之间容易发生正分离,因为它们大多是群落的建群种或优势种,具有强的适应能力和竞争能力。从星座图上可清晰地看到种间分离在不同种之间存在一定的差异。另外,引入群落全面分离这一新概念,并应用χ2检验进行检验研究了翅果油树群落中所有物种的全面分离规律。结果表明,翅果油树群落内38个物种互相交错分布,是全面不分离的。 展开更多
关键词 种间分离 最近邻体法 n×n列联 X^2检验 星座图 翅果油树
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历山山核桃(Juglans mandshurica)群落的种间分离 被引量:14
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作者 高昆 张峰 《生态学报》 CAS CSCD 北大核心 2008年第4期1601-1607,共7页
在野外样方调查的基础上,对山西历山山核桃群落35个样方内所有基径≥1cm的乔木和灌木绘制分布图。按照最近邻体法判定每个个体的最近邻体植株,然后用N×N最近邻体列联表及其2×2列联表截表的方法,应用Pielou的分离指数S和χ2检... 在野外样方调查的基础上,对山西历山山核桃群落35个样方内所有基径≥1cm的乔木和灌木绘制分布图。按照最近邻体法判定每个个体的最近邻体植株,然后用N×N最近邻体列联表及其2×2列联表截表的方法,应用Pielou的分离指数S和χ2检验研究山核桃群落所有乔木和灌木的种间分离规律。χ2检验结果表明:历山山核桃群落出现的25个物种共构成的300个种对中,存在显著分离的有294对,存在不显著分离的有6对。结合χ2值对S进行区间划分得出:正分离的112对占37.34%,负分离的28对,占9.33%;随机毗邻160对,占53.33%。负分离多出现在群落的优势种和一些伴生种之间,如山核桃、连翘与金花忍冬、灰栒子,伴生种相对个体少,盖度低,与优势种具有相似的生境要求,较激烈的竞争使得它们相互交错分布,充分利用资源,呈现负分离。较大的植株之间容易发生正分离,如茶条槭和杜梨,因为它们多是群落的建群种或优势种,具有较强的适应力和竞争力。从星座图上可清晰地看到种间分离在不同物种间存在一定差异。25×25最近邻体列联表的χ2检验结果表明:山核桃群落内25个物种是互相交错分布,全面不分离的。此外,种间分离的结果意味着该群落处于演替初期,与目前这一地区受人为和自然干扰严重,群落处于不稳定阶段的事实相符。 展开更多
关键词 种间分离 最近邻体法 n×n最近邻体列联 χ2检验 星座图 山核桃 历山
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Gene Chip Analysis for Rice MicroRNA Response to Low Energy N^+ Beam Radiation
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作者 周晓君 刘旭昊 +1 位作者 郭向萌 押辉远 《Agricultural Science & Technology》 CAS 2010年第9期47-49,共3页
[Objective] The aim of this study was to explore the expression differences of miRNA response to low energy N+ beam radiation in rice.[Method]Three groups of ion beam irradiation rice seeds and untreated rice seeds w... [Objective] The aim of this study was to explore the expression differences of miRNA response to low energy N+ beam radiation in rice.[Method]Three groups of ion beam irradiation rice seeds and untreated rice seeds were selected respectively,and then the total RNA of seedlings after 96 h of germination was extracted at 30 ℃.Agilent gene chip was used to screen the differentially expressed genes of two groups of rice seedlings.The chip contained 510 miRNA probes;and about two times of expression differences between two samples were considered as the threshold range.[Result]14 miRNA molecules showed significant expression differences between the irradiated group and the control group,and all of them were decreased.[Conclusion]The miRNAs showed expression differences between irradiated group and the control group,which might regulate the expression of certain genes to respond to ion irradiation,thus producing physiological,biochemical and phenotypic differences. 展开更多
关键词 nitrogen ion beam Irradiated rice MiRnA Differential expression Gene chip
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Construction and Identification of siRNA Expression Vector Targeting Nucleocapsid Protein N gene of PRRSV 被引量:1
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作者 曹素芳 李明 +4 位作者 王岩 朱赞梅 刘长斗 唐桂芬 肖松云 《Agricultural Science & Technology》 CAS 2009年第4期171-174,共4页
[ Objective] The aim of this study was to investigate the construction and identification of siRNA expression vector targeting nucleocapsid protein N gone of PRRSV. [Method] Three siRNA oligonucleotides targeting nucl... [ Objective] The aim of this study was to investigate the construction and identification of siRNA expression vector targeting nucleocapsid protein N gone of PRRSV. [Method] Three siRNA oligonucleotides targeting nucleocapsid protein N gone sequence of PRRSV were designed or synthesized, and then inserted into CMV promoter downstream to clone into pSilencer 4,1 -CMV eukaryotic expression vector. The recombinant expression vector was identified by enzyme digestion and DNA sequencing. [ Result] The results showed that the siRNA interference recombinant plasmid vector pSilencer-N targeting nucleocapsid protein gone expression had been successfully constructed. [ Conclusion] This study lays a foundation for studies on the controlling PRRSV by RNA interference technique . 展开更多
关键词 PRRSV nucleocapsid protein n SIRnA Expression vector
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高危人群压疮评估表临床应用 被引量:4
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作者 纪淑欣 《护理实践与研究》 2009年第16期103-104,共2页
关键词 压疮预防 临床应用 高危人群 评估 危险因素评估量 局部组织 血液循环障碍 n
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Functional expression of opioid receptor-like receptorand its endogenous specific agonist nociceptin/orphanin FQ during mouse embryogenesis
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作者 WU YA LAN GUO HUANG FAN +4 位作者 JIAN ZHAO YIZHANG TIAN HUA ZHOU LAN MA GANG PEI(Shanghai Institute of Cell Biology, Chinese Academy ofSciences, Shanghai 200031, ChinaShanghai Medical University, Shanghai 200032, China) 《Cell Research》 SCIE CAS CSCD 1997年第2期207-215,共9页
Expression of opioid receptor-like receptor (ORL1)and its endogenous peptide agonist nociceptin/orphaninFo (N/OFQ) during mouse embryogenesis have been investigated. Transcripts of ORL1 and N/OFQ were detected by RT-P... Expression of opioid receptor-like receptor (ORL1)and its endogenous peptide agonist nociceptin/orphaninFo (N/OFQ) during mouse embryogenesis have been investigated. Transcripts of ORL1 and N/OFQ were detected by RT-PCR in mouse brain of day 8 embryo (E8)and the expression continued afterwards. Northern blotanalysis revealed abundant expression of ORL1 at postnatal day 1 (P1) and N/OFQ at E17 and P1 in the brain butnone was detected in other embryonic tissues. The presence of functional ORL1 in mouse embryonic brain wasalso confirmed by specific binding of [3H] N/OFQ (kd=1.3±0.5 nM and Bmax = 72±9 fmol/mg protein) as wellas by N/OFQ-stimulated G protein activation. 展开更多
关键词 Opioid receptor-like receptor (ORL_1) nociceptin/orphanin FQ (n/OFQ) mouse embryogenesis functional expression
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Municipal Landfill as a Source of Fulvic Acids Polluting Water
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作者 Tomasz Orliński Anna M. Anielak 《Journal of Civil Engineering and Architecture》 2018年第6期462-469,共8页
The FAs (fulvic acids) belong to natural organic contaminants that are commonly found in different environments. In the process of oxidation and disinfection FAs are precursors of toxic substances, which cause a pro... The FAs (fulvic acids) belong to natural organic contaminants that are commonly found in different environments. In the process of oxidation and disinfection FAs are precursors of toxic substances, which cause a problem in many water treatment plants. In the sewage treatment plants, FAs are not biodegradable and together with purified wastewater and are discharged into surface waters. One of important source of the formation of FAs is the municipal landfill. In this thesis the authors test the amount of soluble fulvic acids present in the leachate of Barycz landfill in Krakow. The extracted FAs were subjected to a detailed analysis for the content of metals and IR spectrum analysis has also been done. Basing on elemental composition the C/O, C/H and C/N ratios have been determined. The obtained data were compared with the characteristics specified in the literature. 展开更多
关键词 Fulvic acids humic acids humic substances LAnDFILL LEACHATE WASTE
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Are polymorphisms of N-acetyltransferase genes susceptible to primary liver cancer in Luoyang, China? 被引量:3
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作者 Xiu-FengZhang Jian-ChaoBian +6 位作者 Xiao-YanZhang Zhu-MeiZhang FengJiang Qi-MinWang Qi-JunWang Yan-YanCao Bo-MingTang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第10期1457-1462,共6页
AIM: To identify whether the polymorphisms of the Nacetyltransferase (NAT) genes are susceptible to primary liver cancer (PLC) in Luoyang, a PLC low-incidence area of China.METHODS: The NAT1 and NAT2 genotypes of 96 P... AIM: To identify whether the polymorphisms of the Nacetyltransferase (NAT) genes are susceptible to primary liver cancer (PLC) in Luoyang, a PLC low-incidence area of China.METHODS: The NAT1 and NAT2 genotypes of 96 PLC cases and 173 controls were determined by PCR-RFLP.Both interaction between NAT1 or NAT2 and environmental risk factors were analyzed based on case control study.RESULTS: Compared to the control group, the frequencies of alleles NAT1*3, NAT1*4, NAT1*10, NAT1*14B and alleles NAT2*4, NAT2*6, NAT2*7 in PLC group showed no statistically significant difference (x2 = 2.61 and 4.16,respectively, both P>0.05). The frequencies of NAT1 genotypes NAT1*3/*3, NAT1*3/*4, NAT1*3/*10,NAT1*3/*14B, NAT1*4/*4, NAT1*4/*10, NAT1*4/*14B,NAT1*10/*10, NAT1*10/*14B, and NAT2 genotypes NAT2*4/*4, NAT2*4/*6, NAT2*4/*7, NAT2*6/*6,NAT2*6/*7 and NAT2*7/*7 also had no statistically significant difference between the two groups (x2 = 11.86 and 2.94respectively both, P>0.05). Neither the frequencies of rapid and slow NAT1 acetylators nor the frequencies of rapid and slow NAT2 acetylators were significantly different between the two groups (x2 = 0.598 and 0.44,respectively, both P>0.05). The interaction betweenNAT1*10 and occupational exposures was found significant with an odds ratio of 3.40 (x2 = 8.42, P = 0.004,OR 95%CI:1.03-11.22). But no interaction was found between NAT2 and any environmental risk factors.CONCLUSION: The polymorphisms of NAT1 and NAT2are not susceptible to PLC in Luoyang. Allele NAT1*10interacts with occupational exposures. 展开更多
关键词 POLYMORPHISMS n-acetyltransferase genes Primary liver cancer
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NAT2*6A, a haplotype of the N-acetyltransferase 2 gene, is an important biomarker for risk of anti-tuberculosis drug-induced hepatotoxicity in Japanese patients with tuberculosis 被引量:21
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作者 Norihide Higuchi Naoko Tahara +14 位作者 Katsunori Yanagihara Kiyoyasu Fukushima Naofumi Suyama Yuichi Inoue Yoshitsugu Miyazaki Tsutomu Kobayashi Koh-ichiro Yoshiura Norio Niikawa, Chun-Yang Wen, Hajime Isomoto,Saburou Shikuwa, Katsuhisa Omagari, Yohei Mizuta, Shigeru Kohno, Kazuhiro Tsukamoto Norio Niikawa Chun-Yang Wen Hajime Isomoto Saburou Shikuwa Katsuhisa Omagari Yohei Mizuta Shigeru Kohno Kazuhiro Tsukamoto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第45期6003-6008,共6页
AIM: To investigate an association between N -acetyltransferase 2 (NAT2 )-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treat... AIM: To investigate an association between N -acetyltransferase 2 (NAT2 )-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treated with anti-TB drugs including INH. The frequencies and distributions of single nucleotide polymorphisms, haplotypes, and diplotypes of NAT2 were determined by the PCR-restriction fragment length polymorphism method, and the results were compared between TB patients with and without adverse effect, using multivariate logistic regression analysis.RESULTS: Statistical analysis revealed that the frequency of a variant haplotype, NAT2*6A , was signifi cantly increased in TB patients with hepatotoxicity, compared with those without hepatotoxicity [P = 0.001, odds ratio (OR) = 3.535]. By contrast, the frequency of a wild-type (major) haplotype, "NAT2*4", was signif icantly lower in TB patients with hepatotoxicity than those without hepatotoxicity (P < 0.001, OR = 0.265). There was no association between NAT2-haplotypes and skin rash or eosinophilia. CONCLUSION: The present study shows that NAT2 is one of the determinants of anti-TB drug-induced hepatotoxicity. Moreover, the haplotypes, NAT2*4 and NAT2*6A, are useful new biomarkers for predicting anti- TB drug-induced hepatotoxicity. 展开更多
关键词 TUBERCULOSIS Anti-tuberculosis drugs Drug-induced hepatotoxicity nAT2-haplotype DnA-baseddiagnosis
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Surface regulated Ni nanoparticles on N-doped mesoporous carbon as an efficient electrocatalyst for CO_(2)reduction 被引量:3
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作者 Min Wang Qi Xie +3 位作者 Huimin Chen Guangbo Liu Xuejing Cui Luhua Jiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第12期2306-2312,共7页
Low cost,highly selective and efficient electrocatalysts for CO_(2)reduction reaction(CO_(2)RR)is crucial for lowering the global carbon footprint and mitigating energy shortages.Here,we first report a highly selectiv... Low cost,highly selective and efficient electrocatalysts for CO_(2)reduction reaction(CO_(2)RR)is crucial for lowering the global carbon footprint and mitigating energy shortages.Here,we first report a highly selective and efficient electrocatalyst for CO_(2)RR to CO using a surface-regulated Ni nanoparticles supported on N-doped CMK-3(N,O-Ni/CMK3).Compared with most Ni metal catalysts previously reported with severe competitive hydrogen evolution during the CO_(2)RR,the N,O-Ni/CMK3 catalyst presents a superior CO faradaic efficiency of about 97%,a high CO partial current density(13.01 mA cm^(-1))and turnover frequency(4.25 s^(–1)).The comprehensive characterization provides evidence that the N,O co-regulated Ni acts as the active center.Taking advantage of the N,O co-regulated chemical environment,N,O-Ni/CMK3 also displays a decent stability at negative potentials.Our work paves a novel approach for developing transition metal catalysts for CO_(2)RR with enhanced activity and selectivity via regulating surface chemical environment. 展开更多
关键词 CO_(2)electro-reduction reaction ni nanoparticle n-doped mesoporous carbon Surface regulation High selectivity
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Cloning and expression of follistatin gene in half-smooth tongue sole Cynoglossus semilaevis during the reproduction cycle 被引量:1
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作者 温海深 司玉凤 +2 位作者 张远青 何峰 李吉方 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期299-308,共10页
Follistatin(FST) is a monomeric glycoprotein highly enriched in cysteines and belongs to TGF-β superfamily. FST can suppress the secretion of follicle-stimulating hormone and plays a vital role in the reproduction of... Follistatin(FST) is a monomeric glycoprotein highly enriched in cysteines and belongs to TGF-β superfamily. FST can suppress the secretion of follicle-stimulating hormone and plays a vital role in the reproduction of vertebrates. We used rapid amplification of cDNA ends technology to clone the FST gene of half-smooth tongue sole,Cynoglossus semilaevis. We characterized its phylogenetic context and expression patterns to elucidate its function in the breeding season. The full-length sequence of FST is 1 455 bp and encodes a protein of 321 amino acids. We investigated the expression pattern of FST in C. semilaevis at different stages of reproduction using reverse transcription-polymerase chain reaction(RTPCR). FST m RNA was expressed in all 13 tissues analyzed,and was expressed at high levels in gonad and at slightly lower levels in gill and brain. During the reproductive cycle of C. semilaevis,the transcript level of FST was the highest in the perinucleolus stage,decreased in the primary yolk stage,slightly increased in the tertiary yolk stage,and then reduced to a minimal level in the atretic follicles stage of the ovary. We concluded that FST suppressed follicle-stimulating hormone,which stimulated oocyte development. However,no significant variation was observed across all stages of testis development,although the expression level in the spermatogenesis stage was relatively low,which may result from the regulation of FST by aromatase. 展开更多
关键词 Cynoglossus semilaevis follistatin (FST) CLOnInG gene expression
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Synthesis and characterization of 2-hydroxy-N-methyl-N-phenyl-acetamide
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作者 周忠诚 舒万艮 《Journal of Central South University of Technology》 2002年第1期25-29,共5页
2-hydroxy N methyl N phenyl acetamide was synthesized by using N methylaniline, chloracetyl chloride, anhydrous sodium acetate and methanol through the acetylation, esterfication and ester interchange steps. The acety... 2-hydroxy N methyl N phenyl acetamide was synthesized by using N methylaniline, chloracetyl chloride, anhydrous sodium acetate and methanol through the acetylation, esterfication and ester interchange steps. The acetylation of N methylaniline with chloracetyl chloride, catalyzed by triethylamide with mole ratio n (C 6H 5NHCH 3)∶ n (ClCH 2C(O)Cl)∶ n (N(C 2H 5) 3)=1∶1.05∶1, the yield of 2 chloro N methyl N phenyl acetamide(Ⅰ) was 93.8%; Then the esterification of Ⅰ with anhydrous sodium acetate in the presence of phase transfer catalyst tetrabutyl ammonia bromide gave 97.3% yield of 2 acetoxyl N methyl N phenyl acetamide (Ⅱ); The ester interchange of with methanol catalyzed by potassium hydroxide gave 2 hydroxy N methyl N phenyl acetamide (Ⅲ) in 96.4% yield. And the total yield was 88.0%. IR and MS spectroscopy of products were analyzed and their characteristic peaks were assigned. Combining the results of elemental analysis, the molecular structure of Ⅰ, Ⅱ and Ⅲ was identified. 展开更多
关键词 -n-methyl n phenyl acetamide synthesis ACETYLATIOn esterfication ester interchange characterization
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Purification and characterization of iron-cofactored superoxide dismutase from Enteromorpha linza
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作者 吕明生 蔡阮鸿 +4 位作者 王淑军 刘兆普 焦豫良 房耀维 张小昕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第6期1190-1195,共6页
A superoxide dismutase was purified from Enteromorpha linza using a simple and safe procedure, which comprised phosphate buffer extraction, ammonium sulphate precipitation, ion exchange chromatography on Q-sepharose c... A superoxide dismutase was purified from Enteromorpha linza using a simple and safe procedure, which comprised phosphate buffer extraction, ammonium sulphate precipitation, ion exchange chromatography on Q-sepharose column, and gel filtration chromatography on Superdex 200 10/300GL. The E. linza superoxide dismutase (E/SOD) was purified 103.6-fold, and a yield of 19.1% and a specific activity of 1 750 U/rag protein were obtained. The SDS-PAGE exhibited E/SOD a single band near 23 kDa and the gel filtration study showed E/SOD's molecular weight is near 46 kDa in nondenatured condition, indicating it's a homodimeric protein. E/SOD is an iron-cofactored superoxide dismutase (Fe-SOD) because it was inhibited by hydrogen peroxide, insensitive to potassium cyanide. The optimal temperature for its maximal enzyme activity was 35℃, and it still had 29.8% relative activity at 0℃, then E/SOD can be classified as a cold-adapted enzyme. E/SOD was stable when temperature was below 40℃ or the pH was within the range of 5 10. The first 11 N-terminal amino acids orE/SOD were ALELKAPPYEL, comparison of its N-terminal sequence with other Fe-SOD N-terminal sequences at the same position suggests it is possibly a chloroplastic Fe-SOD. 展开更多
关键词 iron-cothctored superoxide dismutase Enteromorpha linza PURIFICATIOn enzymatic characterization
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Expression Variability of Carbohydrates at the Cell Wall Surface of Aspergillus Species and in Vitro Susceptibility to Amphotericin B, Voriconazole and Itraconazole
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作者 André Ferraz Goiana Leal Eduardo Isidoro Cameiro Beltrao +1 位作者 Almir Goncalves Wanderley Rejane Pereira Neves 《Journal of Life Sciences》 2014年第4期358-363,共6页
This study evaluated the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surface of Aspergillus species using lectins and the in vitro antifungal activity of AMB (amph... This study evaluated the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surface of Aspergillus species using lectins and the in vitro antifungal activity of AMB (amphotericin B), VOR (voriconazole) and ITC (itraconazole). Con A (Concanavalin A), WGA (wheat germ agglutinin), UEA-I (Ulex europeus agglutinin I) and PNA (peanut agglutinin), all conjugated with horseradish peroxidase, were used. For the susceptibility tests, sterilized fiat-bottomed 96-well microtitre plates were used and the procedures were followed of the Clinical and Laboratory Standard Institute. The inoculum was added to the wells with the tested drugs and the plates were incubated at 25 ℃ for 48 h before reading the results to determine the MIC (minimal inhibitory concentration) of AMB, VOR and ITC. All Aspergillus strains showed low MIC for AMB (0.031-1 μg/mL) and ITC (0.031-0.25μg/mL). However, the isolates were less susceptible to VOR, for which the MIC ranged from 4 to 16 μg/mL. The results of this study indicate that the expression of N-acetyl-D-glucosamine and glucose/mannose on the cell wall surface of the Aspergillus species evaluated showed greater stability of expression in the fungal growth both in vitro and in parasitism. 展开更多
关键词 Cell wall carbohydrates LECTInS ASPERGILLUS antifungal activity.
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Synthesis and Properties of Novel Surface Active Maleic Monomer Containing Phosphate Group
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作者 Mykola Borzenkov Yuri Galadjun +1 位作者 Natalia Mitina Orest Hevus 《Journal of Chemistry and Chemical Engineering》 2014年第5期493-500,共8页
A novel surface active monomer (surfmer) containing poly(ethylene glycol) chain and terminated phosphate group was synthesized. The copolymerization of synthesized surfmer with NVP (N-vinylpyrrolidone) and with ... A novel surface active monomer (surfmer) containing poly(ethylene glycol) chain and terminated phosphate group was synthesized. The copolymerization of synthesized surfmer with NVP (N-vinylpyrrolidone) and with NVP and VEP (5-tert-butylperoxy-5-methyl-2-hexene-3-yne monomer) led to formation of corresponding surface-active copolymers. The capability of application of resulted copolymers as surface active macroinitiators of emulsion polymerization of styrene and as components of polymeric scaffolds was investigated. 展开更多
关键词 Surface active monomers surface tension surface active polymers emulsion polymerization polymeric scaffolds.
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