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Study on the Thermodynamic Stabilities of Te-Substituted Di-n-butyltellurium Ylide

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chinese Chemical Letters 1998年第10期9卷 897-898页

作者： Bo LIU jin pei cheng chi zhong xia(Department of Chemistry, Nankai University, Tianjin 300071 Institute of Molecular Science and Depotment of Chemistry, Shanxi University,Taiyuan 030006) Nankai Univ Dept Chem Tianjin 300071 Peoples R China Shanxi Univ Inst Mol Sci Taiyuan 030006 Peoples R China Shanxi Univ Dept Chem Taiyuan 030006 Peoples R China

Eight Te-substituted di-n-butyltellurium bromides were synthesized. Their equilibrium acidities (pK(A)) were determined in DMSO at 25 degrees C and the thermodynamic stabilities of the corresponding tellurium ylide ca... 详细信息

关键词： tellurium ylide stability pK(A)

纳米氧化钛复合改性提升聚醚酰亚胺真空沿面闪络特性的物理机制分析

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中国电机工程学报 2024年第14期44卷 5810-5820,I0032页

作者：曾嘉凯李倬凡张妍刘霞杨柳青刘文凤迟晓红程璐电力设备电气绝缘国家重点实验室(西安交通大学) 陕西省西安市710049

聚醚酰亚胺是重要的航天器用绝缘材料。提升聚醚酰亚胺的沿面绝缘性能并探究沿面闪络的物理机制具有重要意义。该研究通过纳米氧化钛复合改性有效地将聚醚酰亚胺的真空沿面闪络电压提高19.25%。通过表征纳米复合前后材料的表面形貌、表... 详细信息

聚醚酰亚胺是重要的航天器用绝缘材料。提升聚醚酰亚胺的沿面绝缘性能并探究沿面闪络的物理机制具有重要意义。该研究通过纳米氧化钛复合改性有效地将聚醚酰亚胺的真空沿面闪络电压提高19.25%。通过表征纳米复合前后材料的表面形貌、表面释气和表面电荷输运特性发现,表面气体吸附量随着TiO_(2)含量的升高而增大,而深陷阱能级和表面电阻率与闪络电压呈正相关关系。分析认为,纳米复合改性后气体吸附特性变化不足以影响真空沿面闪络。纳米复合改性提高真空沿面闪络电压的根本原因在于适量的TiO_(2)能提高材料的表面电阻率和深陷阱能级,二者的提高阻碍电极处电荷的注入和表面电子发射,进而造成电子倍增过程受阻。当电子倍增过程受阻时,介质表面需要更大的能量去释放更多的内部溶解气体或使介质分解产生更多气体以便碰撞电离形成足够强度的电子崩,因此沿面闪络电压有所提升。

关键词：聚醚酰亚胺纳米复合真空闪络表面陷阱表面释气

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桑叶黄酮对水牛泌乳性能、氨基酸代谢和血清生化指标的影响

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饲料研究 2024年第8期47卷 8-13页

作者：李孟伟彭丽娟郭艳霞韦科龙钟华配罗华杨承剑广西壮族自治区水牛研究所农业农村部(广西)水牛遗传繁育重点实验室广西南宁530001

试验旨在研究桑叶黄酮对泌乳水牛血清氨基酸代谢、血清生化指标和泌乳性能的影响。试验选取泌乳量接近的泌乳中期水牛20头,随机分为2组,每组10个重复,每个重复1头水牛。对照组饲喂基础饲粮,试验组饲喂基础饲粮+45 g/(头·d)桑叶黄酮。... 详细信息

试验旨在研究桑叶黄酮对泌乳水牛血清氨基酸代谢、血清生化指标和泌乳性能的影响。试验选取泌乳量接近的泌乳中期水牛20头,随机分为2组,每组10个重复,每个重复1头水牛。对照组饲喂基础饲粮,试验组饲喂基础饲粮+45 g/(头·d)桑叶黄酮。试验期5 w。结果显示,饲喂桑叶黄酮能够显著降低血清低密度脂蛋白含量(P<0.05),显著提高血清胰岛素含量(P<0.05),显著降低血清蛋氨酸含量(P<0.05),显著提高水牛泌乳量以及乳蛋白、乳脂肪含量(P<0.05)。研究表明,桑叶黄酮通过调控血清氨基酸和脂质代谢提高了水牛的泌乳性能。

关键词：桑叶黄酮氨基酸泌乳性能水牛

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Efficient strategies for changing the diapause character of silkworm eggs and for the germline transformation of diapause silkworm strains

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Insect Science 2012年第2期19卷 172-182页

作者： Ai-Chun Zhao Ding-pei Long San-Yuan Ma Long-xia Xu Mei-Rong Zhang Fang-Yin Dai Qing-You xia cheng Lu zhong-Huai xiang The Key Sericultural Laboratory of Agricultural Ministry Institute of Sericulture and Systems BiologySouthwest UniversityChongqingChina

To overcome the disadvantages of current silkworm Bombyx mori transgenic technology, such as costly and time-consuming to maintain non-diapause transgenic silkworms, we report here on the development of treatments for the germline transformation of diapause silkworm strains. Our results showed that HC1 treatment within 3 h of oviposition was able to prevent the diapause of eggs from Japanese lineage diapause silkworm strains and was also suitable for germline transformation of the same strains. By incu- bating developing mother eggs from chinese lineage diapause silkworm strains at 15℃ （15℃-IME）, we were able to prevent the diapause of their daughter eggs; a similar strategy （15℃-IMES） for the germline transformation of the same strains was that the mother eggs were incubated at 15℃, and the daughter eggs were then microinjected according to the conventional microinjection methods used for non-diapause eggs. By combining tempera- ture and light controls, the improved 15℃-IMES strategy prevented diapause in daughter eggs, and also enabled the germline transformation of both Japanese and chinese lineage diapause silkworm strains. Although each of the strategies developed here has advantages and disadvantages, we suggest that the 15℃-IMES strategy is a good reference for the establishment of germline transformation technologies of other egg diapause insects. These new strategies for the efficient germline transformation of diapause silkworm strains are likely to improve the practical use of silkworm transgenic lines in sericulture and also highlight silkworm functional genomics research and its modeling.

关键词： Bombyx mori diapause functional genomics gerrnline transformation insect piggyBac

Tetrahydrofolate coenzyme models I·Synthesis of l-methyl-2-phenyl-3-aryl imidazoliniumiodide and benzylildyne(phenyl-substitutef one carbon unit)transfer reactions

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chinese Journal of Chemistry 1990年第4期8卷 333-339页

作者： xia, chi-zhong ZHOU, pei-Wen DING, jing-Fan The Institute of Molecular Science, Department of Chemistry,Shanxi University, Taiyuan, 030006 Institute of Molecular Science Department of Chemistry Shanxi University Taiyuan 030006

Four 1, 2, 3-trisubstituted imidazolinium iodides which were used as 5,10-^+CPh-THF model (7-10) at formic acid oxidation level were synthesized. The benzylidyne group (phenyl- substituted one carbon unit)transfer reactions from these compounds to Grignard reagent were in- vestigated, and the reactions of these compounds with KBH_4 and NaOH were also studied.

关键词： Synthesis of l-methyl-2-phenyl-3-aryl imidazoliniumiodide and benzylildyne Tetrahydrofolate coenzyme models I phenyl-substitutef one carbon unit)transfer reactions

甲基取代的甲酸态的四氢叶酸辅酶模型的合成及其取代碳单元转移反应

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高等学校化学学报 1998年第7期19卷 1095-1100页

作者：赵炳筠夏炽中程津培南开大学化学系山西大学化学系

以乙二胺和乙酰胺为原料，经４步反应合成了碘化１，２－二甲基－３－间（或对）－硝基苯磺酰基咪唑啉（２ａ，２ｂ），以２ａ和２ｂ作为甲基取代的甲酸态四氢叶酸辅酶模型，同单亲核中心的氮亲核体（对甲苯胺，对甲氧基苯胺等）和碳亲... 详细信息

以乙二胺和乙酰胺为原料，经４步反应合成了碘化１，２－二甲基－３－间（或对）－硝基苯磺酰基咪唑啉（２ａ，２ｂ），以２ａ和２ｂ作为甲基取代的甲酸态四氢叶酸辅酶模型，同单亲核中心的氮亲核体（对甲苯胺，对甲氧基苯胺等）和碳亲核体（丙二腈）反应得到次乙基单元（ＣＨ３—Ｃ）转移的中间体产物；与双亲核中心的亲核体（邻苯二胺，邻氨基酚）反应得到次乙基单元完全转移的产物．

关键词：四氢叶酸辅酶模型一碳单元咪唑啉盐转移反应

Incidence and risk factor analysis for swelling after apical microsurgery

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World Journal of Clinical Cases 2022年第26期10卷 9303-9309页

作者： cheng Bi Si-Qi xia Yu-chi Zhu Xin-Zhu Lian Li-Jun Hu Chen-Xing Rao Hai-Bin jin xiao-Dan Shang Fei-Fan jin jing-Yu Li pei Zheng Shu-Hua Wang School of Stomatology Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina VIP Center Hangzhou Stomatology HospitalHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Swelling after apical microsurgery is a postoperative reaction and may reduce quality of life during *** To evaluate periapical swelling after apical microsurgery and determine potential risk *** Ninety-eight apical microsurgery patients were selected for this *** surgery,bone shadow volume and density of pathological tissue were measured by cone beam computed *** other variables(age,gender,operative teeth number,fistula,preoperative swelling,drug use and preoperative root canal treatments)were assessed during *** degree was confirmed by questionnaires for patients on postoperative days 1,7,14 and *** analyses were performed to identify predictors for *** Majority of patients reported moderate(45.9%)or severe(34.7%)swelling on day 1,and moderate(44.9%)or mild(45.9%)on postoperative day ***-nine percent of patients had no or mild swelling on postoperative day *** average swelling level peaked on day 1 postoperatively and gradually *** statistical significance,age,bone shadow volume and density of pathological tissue acted as predictors of swelling(P0.05).CONCLUSION Younger patients with larger shadow volume and density were significantly more likely to develop swelling after apical microsurgery.

关键词： Apical microsurgery Swelling Incidence Risk factor Prognosis

Prostate cancer prediction forest algorithm that takes using the random into account transrectal ultrasound findings, age, and serum levels of prostate-specific antigen

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Asian Journal of Andrology 2017年第5期19卷 586-590页

作者： Li-Hong xiao pei-Ran Chen zhong-Ping Gou Yong-zhong Li Mei Li Liang-cheng xiang Ping Feng Institute of Clinical Trials West China Hospital Sichuan University Chengdu China Department of Epidemiology and Biostatistics West China School of Public Health Sichuan University Chengdu China Department of Ultrasound West China Hospital Sichuan University Chengdu China

The aim of this study is to evaluate the ability of the random forest algorithm that combines data on transrectal ultrasound findings, age, and serum levels of prostate-specific antigen to predict prostate carcinoma. Clinico-demographic data were analyzed for 941 patients with prostate diseases treated at our hospital, including age, serum prostate-specific antigen levels, transrectal ultrasound findings, and pathology diagnosis based on ultrasound-guided needle biopsy of the prostate. These data were compared between patients with and without prostate cancer using the chi-square test, and then entered into the random forest model to predict diagnosis. Patients with and without prostate cancer differed significantly in age and serum prostate-specific antigen levels （P 〈 0.001）, as well as in all transrectal ultrasound characteristics （P 〈 0.05） except uneven echo （P = 0.609）. The random forest model based on age, prostate-specific antigen and ultrasound predicted prostate cancer with an accuracy of 83.10%, sensitivity of 65.64%, and specificity of 93.83%. Positive predictive value was 86.72%, and negative predictive value was 81.64%. By integrating age, prostate-specific antigen levels and transrectal ultrasound findings, the random forest algorithm shows better diagnostic performance for prostate cancer than either diagnostic indicator on its own. This algorithm may help improve diagnosis of the disease by identifying patients at high risk for biopsy.

关键词： diagnosis prostate cancer prostate-specific antigen random forest algorithm transrectal ultrasound characteristics

Performance of the CMA-GD Model in Predicting Wind Speed at Wind Farms in Hubei, china

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Journal of Tropical Meteorology 2023年第4期29卷 473-481页

作者：许沛华成驰王文陈正洪钟水新张艳霞 Hubei Meteorological Service Center Wuhan 430079 China Faculty of Artificial Intelligence Education School of Educational Information TechnologyCentral China Normal UniversityWuhan 430079 China Hubei Energy Group New Energy Development Co. Ltd.Wuhan 430069 China Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction/Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510641 China

This study assesses the predictive capabilities of the CMA-GD model for wind speed prediction in two wind farms located in Hubei Province,*** observed wind speeds at the height of 70m in wind turbines of two wind farms in Suizhou serve as the actual observation data for comparison and *** the same time,the wind speed predicted by the EC model is also included for comparative *** results indicate that the CMA-GD model performs better than the EC model in Wind Farm *** CMA-GD model exhibits a monthly average correlation coefficient of 0.56,root mean square error of 2.72 m s^(-1),and average absolute error of 2.11 m s^(-1).In contrast,the EC model shows a monthly average correlation coefficient of 0.51,root mean square error of 2.83 m s^(-1),and average absolute error of 2.21 m s^(-1).Conversely,in Wind Farm B,the EC model outperforms the CMA-GD *** CMA-GD model achieves a monthly average correlation coefficient of 0.55,root mean square error of 2.61 m s^(-1),and average absolute error of 2.13 m s^(-1).By contrast,the EC model displays a monthly average correlation coefficient of 0.63,root mean square error of 2.04 m s^(-1),and average absolute error of 1.67 m s^(-1).

关键词： CMA-GD wind speed prediction wind farm root mean square error performance evaluation