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超球谐展开的收敛行为He原子的^3S态
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作者 王沂轩 弭云杰 +1 位作者 邓从豪 黄海兰 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1997年第11期1829-1832,共4页
利用相关函数一超球谐-广义Laguerre函数方法(CFHHGLF),研究He原子3S态波函数向超球谐函数展开的收敛行为.截止于l=0,1,2的超球谐函数给出的本征能分别与组态相互作用(CI)的s-、sp-、spd-极限能一致.仅用44个超球谐函数,便... 利用相关函数一超球谐-广义Laguerre函数方法(CFHHGLF),研究He原子3S态波函数向超球谐函数展开的收敛行为.截止于l=0,1,2的超球谐函数给出的本征能分别与组态相互作用(CI)的s-、sp-、spd-极限能一致.仅用44个超球谐函数,便得到了与精确的HylleraasCI变分能量小数点后第5位的23S、33S和43S态本征能吻合. 展开更多
关键词 超球谐 波函数 CFHHGLF 氦原子 3s态
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超球谐展开的收敛行为—He原子的^1S态
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作者 王沂轩 弭云杰 +1 位作者 邓从豪 卢秀慧 《科学通报》 EI CAS CSCD 北大核心 1998年第10期1119-1119,共1页
关键词 超球谐展开 收敛行为 氦原子 本征能 1s态
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利用强度依赖耦合的Jaynes-Cummings模型的时间演化制备类Schrdinger猫态(英文)
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作者 宋克慧 《光子学报》 EI CAS CSCD 1999年第10期883-887,共5页
提出了制备压缩相干态的叠加态,亦即类Schrodnger猪态的方案,该方案是基于强度依赖耦合的Jaynes-Cummings模型在远离共振极限下的时间演化而设计的.
关键词 压缩相干 叠加 时间演化 s J-C模型
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Differential utilization and speciation transformation of orthorhombic α-S_8 and amorphous μ-S by substrate-acclimated mesophilic Acidithiobacillus ferrooxidans 被引量:2
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作者 刘红昌 夏金兰 +3 位作者 聂珍媛 郑雷 马陈燕 赵屹东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期3096-3102,共7页
The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the ene... The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the energy source α-S8 or μ-S,respectively.The results of cell growth and sulfur oxidation behavior showed that the strain grown on α-S8 entered slowly(about 1 d later) into the exponential phase,while grew faster in the exponential phase and attained higher maximal cell density and lower p H value than that on μ-S.After bio-corrosion,both of the two sulfur samples were evidently eroded and modified by A.ferrooxidans cells.After growth of A.ferrooxidans,the surface composition of amorphous μ-S became 63.1% μ-S and 36.9% α-S8,and that of orthorhombic α-S8 became 68.3% α-S8 and 31.7% μ-S,while the surface compositions of α-S8 and μ-S in sterile experiment were not changed,indicating that these two elemental sulfur species can be interconverted by A.ferrooxidans. 展开更多
关键词 sulfur utilization sulfur speciation transformation α-s8 μ-s Acidithiobacillus ferrooxidans
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Seismic data denoising based on mixed time-frequency methods 被引量:3
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作者 蔡涵鹏 贺振华 黄德济 《Applied Geophysics》 SCIE CSCD 2011年第4期319-327,371,共10页
Deconvolution denoising in the f-x domain has some defects when facing situations like complicated geology structure, coherent noise of steep dip angles, and uneven spatial sampling. To solve these problems, a new fil... Deconvolution denoising in the f-x domain has some defects when facing situations like complicated geology structure, coherent noise of steep dip angles, and uneven spatial sampling. To solve these problems, a new filtering method is proposed, which uses the generalized S transform which has good time-frequency concentration criterion to transform seismic data from the time-space to time-frequency-space domain (t-f-x). Then in the t-f-x domain apply Empirical Mode Decomposition (EMD) on each frequency slice and clear the Intrinsic Mode Functions (IMFs) that noise dominates to suppress coherent and random noise. The model study shows that the high frequency component in the first IMF represents mainly noise, so clearing the first IMF can suppress noise. The EMD filtering method in the t-f-x domain after generalized S transform is equivalent to self-adaptive f-k filtering that depends on position, frequency, and truncation characteristics of high wave numbers. This filtering method takes local data time-frequency characteristic into consideration and is easy to perform. Compared with AR predictive filtering, the component that this method filters is highly localized and contains relatively fewer low wave numbers and the filter result does not show over-smoothing effects. Real data processing proves that the EMD filtering method in the t-f-x domain after generalized S transform can effectively suppress random and coherent noise of steep dips. 展开更多
关键词 Empirical Mode Decomposition generalized s transform coherent noise random noise noise suppression
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Exclusive Population of n=2 S-states in He-like Uranium by Ionization Process
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作者 Ma Xinwen D.Banas +14 位作者 Th.Sthlker H.F.Beyer F.Bosch A.Br(?)uning-Demian A.Gumberidze S.Hagmann C.Kozhuharov P.H.Mokler R.Mann A.Orsic Muthig D.Sierpowski U.Spillmann S.Tachenov Z.Stachura A.Warczak 《近代物理研究所和兰州重离子加速器实验室年报:英文版》 2002年第1期76-76,共1页
K-shell ionization for Li-like uranium ions in collisions with a N2 target was performed at the ESR storage ring. We found surprisingly that in such close encounters the 2 s electron remain almost unaffected by the co... K-shell ionization for Li-like uranium ions in collisions with a N2 target was performed at the ESR storage ring. We found surprisingly that in such close encounters the 2 s electron remain almost unaffected by the collisions. A dedicated experimental study was conducted by using Li-like uranium ions at an initial energy of 378 MeV/u in order to manifest the situation. In Fig.1 a typical spectrum is shown registered by a Ge(i) 展开更多
关键词 碰撞电离 类氦铀离子 超选择布居 s态 原子物理学 X射线衍射光谱分析 辐射强度
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传导系统中TE/TM偏振模态的辨析
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作者 董国艳 史祎诗 王雅丽 《中国科学院大学学报(中英文)》 CSCD 北大核心 2016年第3期347-353,共7页
电磁波/光传输特性研究中常用TE/TM偏振描述波的传播模式.不同系统中对TE/TM偏振的定义却存在差别,有时还与s/p态混合使用,使研究者在理论和实验研究中产生概念混淆和结果矛盾的问题.本文从电磁理论出发,对传导系统中可能存在的偏振模... 电磁波/光传输特性研究中常用TE/TM偏振描述波的传播模式.不同系统中对TE/TM偏振的定义却存在差别,有时还与s/p态混合使用,使研究者在理论和实验研究中产生概念混淆和结果矛盾的问题.本文从电磁理论出发,对传导系统中可能存在的偏振模式进行深入的推导和分析,解释TE/TM偏振态存在原因和可能状态,对其与s/p态的区别进行比较说明.针对空间偏振态的易混淆问题进行逐一解答. 展开更多
关键词 物理光学 偏振模 TE/TM模 s/p
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沉降槽高度和重泥层高度对稳态沉降底流液固比的影响 被引量:1
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作者 李峰杰 赵海峰 何静宇 《轻金属》 CSCD 北大核心 2018年第1期17-22,共6页
分析了影响稳态沉降底流L/S的主要因素,针对沉降槽有效使用高度和重泥层高度对底流L/S的影响,考虑重力压缩效应,认为底流赤泥粒子(絮团)受压变形为弹性形变,建立了一维稳态沉降数学模型,得到了表征不同高度压力变化系数f(x)=1-p(x)/Es... 分析了影响稳态沉降底流L/S的主要因素,针对沉降槽有效使用高度和重泥层高度对底流L/S的影响,考虑重力压缩效应,认为底流赤泥粒子(絮团)受压变形为弹性形变,建立了一维稳态沉降数学模型,得到了表征不同高度压力变化系数f(x)=1-p(x)/Es的微分方程,求出其隐式函数解,通过迭代法求出数值解,进而得到底流L/S的数值解。计算表明:当沉降槽高度由平底槽的7m提高到高效深锥槽的20m时,底流L/S可下降约1/3;而重泥层高度每提高1m,底流L/S可下降约0.05。 展开更多
关键词 沉降底流L/s 干赤泥真密度 压缩效应
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Noncommutative Singular Black Holes
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作者 S.Hamid Mehdipour 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期845-848,共4页
In this paper, applying the method of coordinate coherent states to describe a noncommutative model of Vaidya black holes leads to an exact (t - r) dependence of solution in terms of the noncommutative parameter σ.... In this paper, applying the method of coordinate coherent states to describe a noncommutative model of Vaidya black holes leads to an exact (t - r) dependence of solution in terms of the noncommutative parameter σ. In this setup, there Js no black hole remnant at long times. 展开更多
关键词 Vaidya black hole noncommutative gravity black hole remnant
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UGT1A1 predicts outcome in colorectal cancer treated with irinotecan and fluorouracil 被引量:34
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作者 Yan Wang Lin Shen +4 位作者 Nong Xu Jin-Wan Wang Shun-Chang Jiao Ze-Yuan Liu Jian-Ming Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第45期6635-6644,共10页
AIM:To evaluate effects of UDP-glucuronosyltransferase1A1(UGT1A1) and thymidylate synthetase(TS) gene polymorphisms on irinotecan in metastatic colorectal cancer(mCRC).METHODS:Two irinotecan-and fluorouracil-based reg... AIM:To evaluate effects of UDP-glucuronosyltransferase1A1(UGT1A1) and thymidylate synthetase(TS) gene polymorphisms on irinotecan in metastatic colorectal cancer(mCRC).METHODS:Two irinotecan-and fluorouracil-based regimens,FOLFIRI and IFL,were selected as second-line therapy for 138 Chinese mCRC patients.Genomic DNA was extracted from peripheral blood samples before treatment.UGT1A1 and TS gene polymorphisms were determined by direct sequencing and restriction fragment length polymorphism,respectively.Gene polymorphisms of UGT1A1*28,UGT1A1*6 and promoter enhancer region of TS were analyzed.The relationship between genetic polymorphisms and clinical outcome,that is,response,toxicity and survival were assessed.Pharmacokinetic analyses were performed in a subgroup patients based on different UGT1A1 genotypes.Plasma concentration of irinotecan and its active metabolite SN-38 and inactive metabolite SN-38G were determined by high performance liquid chromatography.Differences in irinotecan and its metabolites between UGT1A1 gene variants were compared.RESULTS:One hundred and eight patients received the FOLFIRI regimen,29 the IFL regimen,and one irinotecan monotherapy.One hundred and thirty patients were eligible for toxicity and 111 for efficacy evaluation.One hundred and thirty-six patients were tested for UGT1A1*28 and *6 genotypes and 125 for promoter enhancer region of TS.Patients showed a higher frequency of wild-type UGT1A1*28(TA6/6) compared with a Caucasian population(69.9% vs 45.2%).No significant difference was found between response rates and UGT1A1 genotype,although wild-type showed lower response rates compared with other variants(17.9% vs 24.2% for UGT1A1*28,15.7% vs 26.8% for UGT1A1*6).When TS was considered,the subgroup with homozygous UGT1A1*28(TA7/7) and non-3RG genotypes showed the highest response rate(33.3%),while wild-type UGT1A1*28(TA6/6) with non-3RG only had a 13.6% response rate,but no significant difference was found.Logistic regression showed treatment duration was closely linked to clinical response.In toxicity comparison,UGT1A1*28 TA6/6 was associated with lower incidence of grade 2-4 diarrhea(27.8% vs 100%),and significantly reduced the risk of grade 4 neutropenia compared with TA7/7(7.8% vs 37.5%).Wild-type UGT1A1*6(G/G) tended to have a lower incidence of grade 3/4 diarrhea vs homozygous mutant(A/A) genotype(13.0% vs 40.0%).Taking UGT1A1 and TS genotypes together,lower incidence of grade 2-4 diarrhea was found in patients with non-3RG TS genotypes,when TA6/6 was compared with TA7/7(35.3% vs 100.0%).No significant association with time to progression(TTP) and overall survival(OS) was observed with either UGT1A1 or TS gene polymorphisms,although slightly longer TTP and OS were found with UGT1A1*28(TA6/6).Irinotecan PK was investigated in 34 patients,which showed high area under concentration curve(AUC) of irinotecan and SN-38,but low AUC ratio(SN-38G /SN-38) in those patients with UGT1A1*28 TA7/7.CONCLUSION:A distinct distribution pattern of UGT1A1 genotypes in Chinese patients might contribute to relatively low toxicity associated with irinotecan and 5-fluorouracil in mCRC patients. 展开更多
关键词 IRINOTECAN Fluorouracil UDP-glucurono-syltransferaselA1 Thymidylate synthetase Polymor-phisms PHARMACOKINETICs Treatment outcome Toxic-ity Metastatic colorectal cancer
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Glutathione-S-transferase M1 polymorphisms on the susceptibility to esophageal cancer among three Chinese minorities:Kazakh,Tajik and Uygur 被引量:1
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作者 Xiao-Mei Lu Ting Yang +5 位作者 Shu-Yong Xu Hao Wen Xing Wang Zhi-Hui Ren Yan Zhang Wei Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第48期7758-7761,共4页
AIM: To investigate the glutathione-S-transferase M1 (GSTM1) polymorphisms in three Chinese minorities, Kazakh, Uygur, and Tajik; and the pathological significance of GSTM1 polymorphisms in esophageal carcinogenesi... AIM: To investigate the glutathione-S-transferase M1 (GSTM1) polymorphisms in three Chinese minorities, Kazakh, Uygur, and Tajik; and the pathological significance of GSTM1 polymorphisms in esophageal carcinogenesis in Kazakh.METHODS: A total of 1121 blood samples (442 males and 679 females) were obtained from healthy Kazakh (654), Uygur (412) and Tajik (55). Primary esophageal squamous cell cancer (ESCC) tissues from Kazakh were obtained from 116 patients who underwent surgery. GSTM1 polymorphisms were analyzed by a combined approach of PCR and electrophoresis techniques.RESULTS: GSTM1 null genotype was found in 62.63% Uygur, 50.91% Tajik and 47.40% Kazakh. A significantly higher frequency of GSTM1 null genotype in Uygur was observed compared with Kazakh (OR: 1.859, 95% CI: 1.445 -2.391, χ^2 = 23.71, P = 0.000). In addition, GSTM1 null genotype was found in 23.53% of welldifferentiated ESCC in Kazakh, in 49.23% of poorly differentiated ESCC, with a significant difference (OR: 3.152, 95% CI: 1.403-7.080, χ^2 = 8.018, P = 0.007).CONCLUSION: There is a marked difference in the frequency of common GSTM1 null genotype between Uygur and Kazakh. GSTM1 null genotype is associated with differentiation of ESCC in Kazakh. 展开更多
关键词 Glutathione-s-transferase M1 KAZAKH UYGUR TAJIK Esophageal cancer
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Vegetable/fruit, smoking, glutathione S-transferase polymorphisms and risk for colorectal cancer in Taiwan 被引量:4
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作者 Chih-Ching Yeh Ling-Ling Hsieh +2 位作者 Reiping Tang Chung Rong Chang-Chieh Fung-Chang Sung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第10期1473-1480,共8页
AIM: To investigate the colorectal cancer risk associated with polymorphic GSTM1, GSTT1 and GSTP1 and the effect of diet and smoking.METHODS: With consents, genotypes of the genes were determined using PCR methods for... AIM: To investigate the colorectal cancer risk associated with polymorphic GSTM1, GSTT1 and GSTP1 and the effect of diet and smoking.METHODS: With consents, genotypes of the genes were determined using PCR methods for 727 cases and 736sex and age-matched healthy controls recruited at a medical center in the Northern Taiwan. Nurses who were blind to the study hypothesis conducted interviews with study participants for the information of socio-demographic variables, diet and smoking.RESULTS: There was no significant association between GSTM1 genotypes and the disease. Men, not women, with GSTT1 null genotype were at significant risk of colorectal cancer, but limited to rectal tumor, and in men aged 60 years and less. The corresponding association with the GSTP1 with G allele compared to GSTP1 A/A genotype was at borderline significance. Compared to men with GSTT1 present and GSTP1 A/A combined, men with both GSTT1 null and GSTP1 with G allele genotypes were at significant risk (odds ratio (OR) = 1.91, 95% confidence interval (CI) = 1.21-3.02), also limited to the rectal tumor and younger men. The beneficial effects of vegetable/fruit intake on colorectal cancer were much higher for men with GSTT1 present (OR = 0.32, 95%CI = 0.20-0.50) or GSTP1 A/A genotypes (OR = 0.40, 95%CI = 0.25-0.64).These effects remained significant for women. But, the greatest protective effect from vegetable/fruit intake for women was observed in those with GSTT1 null or GSTP1 with G allele genotypes. In addition, non-smoking men benefitted significantly from combined effect of higher vegetable/fruit intake and GSTT1 present or GSTP1 A/A genotypes with OR = 0.17 and 0.21 respectively.CONCLUSION: This study suggests that the GSTT1 gene can modulate the colorectal cancer risk and vegetable/fruit-related colorectal cancer risk, particularly in men of no smoking history. 展开更多
关键词 Colorectal cancer Glutathione s-transferase POLYMORPHIsMs VEGETABLEs sMOKING
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In situ fabrication of Bi_(2)Se_(3)/g-C_(3)N_(4)S-scheme photocatalyst with improved photocatalytic activity 被引量:9
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作者 Rongan He Sijiao Ou +2 位作者 Yexuan Liu Yu Liu Difa Xu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期370-378,共9页
Bismuth selenide(Bi_(2)Se_(3))is an attractive visible-light-responsive semiconductor that can absorb a full range of visible and near-infrared light.However,its poor redox capacity and rapid carrier recombination lim... Bismuth selenide(Bi_(2)Se_(3))is an attractive visible-light-responsive semiconductor that can absorb a full range of visible and near-infrared light.However,its poor redox capacity and rapid carrier recombination limit its application in photocatalytic oxidation.In this study,we adopted Bi_(2)Se_(3)as the couple part of graphitic carbon nitride(g-C_(3)N_(4))to construct a Bi_(2)Se_(3)/g-C_(3)N_(4)composite photocatalyst.Through in situ fabrication,the self-developed Bi2O3/g-C_(3)N_(4)precursor was transformed into a Bi_(2)Se_(3)/g-C_(3)N_(4)heterojunction.The as-prepared Bi_(2)Se_(3)/g-C_(3)N_(4)composite exhibited much higher visible-light-driven photocatalytic activity than pristine Bi_(2)Se_(3)and g-C_(3)N_(4)in the removal of phenol.The enhanced photocatalytic activity was ascribed to the S-scheme configuration of Bi_(2)Se_(3)/g-C_(3)N_(4);this was confirmed by the energy-level shift,photoluminescence analysis,computational structure study,and reactive-radical testing.In the S-scheme heterojunction,photo-excited electrons in the conduction band of g-C_(3)N_(4)migrate to the valence band of Bi_(2)Se_(3)and combine with the excited holes therein.By consuming less reactive carriers,the S-scheme heterojunction can not only effectively promote charge separation,but also preserve more reactive photo-generated carriers.This property enhances the photocatalytic activity. 展开更多
关键词 s-scheme heterojunction Bismuth selenide Graphitic carbon nitride In situ fabrication PHOTOCATALYsIs
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A Symmetric Key Exchange Protocol Bsaed on Virtual S-Box 被引量:2
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作者 YIN Yifeng GAN Yong WEN Heyu LI Tianbao 《China Communications》 SCIE CSCD 2014年第A02期46-52,共7页
Based on the theory of polymorphic virtual S-box, the paper presents a symmetric key exchange protocol to solve the problem of session keys delete shared in the computational complexity temporary trading scenario. Bot... Based on the theory of polymorphic virtual S-box, the paper presents a symmetric key exchange protocol to solve the problem of session keys delete shared in the computational complexity temporary trading scenario. Both parties jointly construct a highly nonlinear SPN core algorithm. The paper the connotation of polymorphic cipher theory, making use of the method of self-compiler based expansion factor to collect random parameter sets held by each of the parties containing its own information 5-tuple private keys array Kpa[5] and Kpb[5].The more efficient polymorphism virtual S-box is constructed. The method of secret split for the public key cryptography features can be implemented by symmetry cipher system. The research results will provide a theoretical basis to solve the key exchange problems for short- term communications partner based on symmetric cryptography. 展开更多
关键词 virtual s-box the virtual iterativefunction (VIF) secrecy sub-systems
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Polymorphism of glutathione S-transferase mu 1 and theta 1 genes and hepatocellular carcinoma in southern Guangxi, China 被引量:8
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作者 Zhuo-LinDeng Yi-PingWei YunMa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第2期272-274,共3页
AIM: Glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism of a wide range of carcinogens, but deletions of the genes are commonly found in the population. The present study w... AIM: Glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism of a wide range of carcinogens, but deletions of the genes are commonly found in the population. The present study was undertaken to evaluate the association between GSTM1 and GSTT1 gene polymorphisms and hepatocellular carcinoma (HCC) risk. METHODS: The genetic polymorphisms were studied at an aflatoxin highly contaminated region in Guangxi, China. Pdymerase chain reaction (PCR) technique was used to detect the presence or absence of the GSTM1 and GSTT1 genes in blood samples. The case group was composed of 181 patients of HCC identified by the pathologists and the control group was composed of 360 adults without any tumor. RESULTS: The frequencies of GSTM1 and GSTT1 null genotypes in the control were 47.8% and 42.7%, while those in the HCC group were 64.6% and 59.7%, respectively. The differences between HCC group and control group were very significant (P<0.01). GSTM1 and GSTT1 combined null genotypes in HCC group and control group were 38.2% and 18.5% respectively, and the difference was significant (P<0.05). CONCLUSION: The GSTM1 and GSTT1 null genotypes are associated with an increased risk of HCC in a special geographic environment. Combination of the two null genotypes in an individual is substantially increased twice the risk of HCC. 展开更多
关键词 Hepatocellular carcinoma Glutathione s-transferase mu 1 Glutathione s-transferase theta 1 POLYMORPHIsM
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Genetic polymorphism of glutathione-S-transferase M1 and T1 in associated with carcinogenesis of hepatocellular carcinoma and nasopharyngeal carcinoma
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作者 Yiping Wei Xidai Long +2 位作者 Ziguang Liu Yun Ma Zhuolin Deng 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第3期138-141,共4页
Objective:The aim of our study was to investigate the distribution of glutathione-S-transferase M1 (GSTM1) and T1 (GSTT1) gene polymorphism in hepatocellular carcinoma (HCC) and nasopharyngeal carcinoma (NPC) patients... Objective:The aim of our study was to investigate the distribution of glutathione-S-transferase M1 (GSTM1) and T1 (GSTT1) gene polymorphism in hepatocellular carcinoma (HCC) and nasopharyngeal carcinoma (NPC) patients in a high risk area in Guangxi Zhuang Autonomous Region,China.Methods:It was a case-control study.The genotypes of GSTM1 and GSTT1 in 181 HCC and 126 NPC patients were compared with 641 matched control.The GSTM1 and GSTT1 genotypes were detected using conventional multiplex PCR method.Results:The frequency of GSTM1 null genotype in HCC,NPC and control groups were 65.2%,61.9% and 47.6% respectively,significant difference between these two cancer groups and control was observed (P < 0.01).The frequency of GSTT1 null genotype in HCC,NPC and control groups were 57.5%,62.7% and 43.1% respectively,significant difference between these two cancer groups and control was observed (P < 0.01).Conclusion:The distributions of GSTM1 and T1 genes are polymorphic in HCC and NPC patients in a high risk area in Guangxi,individuals with GSTM1-null or GSTT1-null would have an increasing risk of developing HCC and NPC,especially when combination with virus infection (HBV or EBV) and absorbed chemical toxin (AFB1 or cigarette). 展开更多
关键词 hepatocellular carcinoma (HCC) nasopharyngeal carcinoma (NPC) glutathione-s-transferase M1 (GsTM1) and T1 (GsTT1) gene
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Diagnosis of Valve-Slap of Diesel Engine with EEMD-EMD-AGST Approach 被引量:3
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作者 ZHENG Xu HAO Zhiyong 《Transactions of Tianjin University》 EI CAS 2012年第1期26-32,共7页
A hybrid of ensemble empirical mode decomposition and empirical mode decomposition (EEMD-EMD) is introduced to diagnose the valve-slap vibration signal,which is relative to the dominant combustion knock vibration sign... A hybrid of ensemble empirical mode decomposition and empirical mode decomposition (EEMD-EMD) is introduced to diagnose the valve-slap vibration signal,which is relative to the dominant combustion knock vibration signal given out by a diesel engine around the top dead center (TDC).The time-frequency representations of intrinsic mode functions (IMFs) decomposed by EEMD-EMD are obtained by adaptive generalized S transform (AGST).A type 493 diesel engine was used for the experiment,and the result indicates that the valve-slap of the diesel engine is serious,and the vibration frequencies are higher than the combustion knock.With EEMD-EMD-AGST approach,the valve-slap can be identified by the vibration analysis of the diesel engine. 展开更多
关键词 diesel engine vibration analysis combustion knock valve-slap ensemble empirical mode decomposi- tion empirical mode decomposition
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Studies on Material Cycling in Evergreen Broad-LeavedForest Ecosystem in Hangzhou: Ⅳ. Uptake, Storageand Return of S by Vegetation
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作者 JIANG QIU-YI HE LI-MING YU YI-WU and CHEN GUO-RUI(Zhejiang Forestry College, Ling’an 311300 (China)) 《Pedosphere》 SCIE CAS CSCD 1994年第1期53-58,共6页
The work was carried out to study the uptake, storage and return of S in the evergreen broad-leaved forestecosystem of Hangzhou in Zhejiang Province, China, based on the annual increments of plants and S contentsper u... The work was carried out to study the uptake, storage and return of S in the evergreen broad-leaved forestecosystem of Hangzhou in Zhejiang Province, China, based on the annual increments of plants and S contentsper unit weight plant organs as well as the measured data about the biological return and decomposition.Results showed that the vegetation layer had an annual S uptake of 55.02kg ha ̄(-1) , which accounted for 15.8% of the total S storage in the vegetation layer. The S uptake was the highest in the arbor layer but thelowest in the shrub layer. The biological return of S was 50% higher than the biological uptake, indicatingthe relatively high cycling efficiency of S. Nevertheless, S had a relatively low rate of biological release, so thatS trended to accumulate in the litter layer. S taken up by plants each year came mostly from precipitationand the reserve of soil. 展开更多
关键词 biological cycling ECOsYsTEM evergreen broad-leaved forest s
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羟乙基甲基纤维素对水泥水化的影响 被引量:21
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作者 张国防 王培铭 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第3期369-373,共5页
利用等温量热法、核磁共振谱(NMR)分析、X射线衍射相分析以及热重差示扫描量热(TG-DSC)分析等方法,研究了羟乙基甲基纤维素及其掺量对水泥浆体水化放热、水化产物以及水化进程的影响.研究表明,羟乙基甲基纤维素能够延缓水泥早期水化,降... 利用等温量热法、核磁共振谱(NMR)分析、X射线衍射相分析以及热重差示扫描量热(TG-DSC)分析等方法,研究了羟乙基甲基纤维素及其掺量对水泥浆体水化放热、水化产物以及水化进程的影响.研究表明,羟乙基甲基纤维素能够延缓水泥早期水化,降低早期水化放热速率和水化放热量,但其对水泥中后期水化则没有明显的延缓作用;羟乙基甲基纤维素与水泥水化产物之间发生了相互作用,使得水泥浆体水化产物C-S-H凝胶中的硅氧四面体由一聚合态向一聚合态和二聚合态共存转变. 展开更多
关键词 水泥浆体 羟乙基甲基纤维素 水化热 水化产物 C—s—H凝胶聚合
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γ(3S)→γ(1S)π^+π^-衰变及一个可能的bq态
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作者 郭奉坤 沈彭年 +1 位作者 姜焕清 平荣刚 《高能物理与核物理》 CSCD 北大核心 2005年第12期1121-1124,共4页
利用手征幺正方法研究了衰变γ(3S)→γ(1S)π+π-,通过引入一个Jp=1+,I=1的中间态,该衰变的π+π-不变质量谱和cosθπ*角分布都能够得到很好的解释.同时,其他γ(nS)各态之间的π+π- 跃迁也能得到很好的描述,通过拟合CLEO的数据,对这... 利用手征幺正方法研究了衰变γ(3S)→γ(1S)π+π-,通过引入一个Jp=1+,I=1的中间态,该衰变的π+π-不变质量谱和cosθπ*角分布都能够得到很好的解释.同时,其他γ(nS)各态之间的π+π- 跃迁也能得到很好的描述,通过拟合CLEO的数据,对这个态的质量和宽度作了预言,该态的夸克组成应该是bbqq。 展开更多
关键词 手征幺正理论 Γ衰变 ππs波末相互作用 四夸克
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