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"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy 被引量:1
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作者 Xiao-Si Hu Yong Wang +5 位作者 Hong-Tao Pan Chao Zhu Shi-Lei Chen Hui-Chun Liu Qing Pang Hao Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期503-510,共8页
BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require furt... BACKGROUND Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment,the feasibility and safety of this approach for laparo-scopic pancreaticoduodenectomy(LPD)require further clinical evaluation and investigation.AIM To explore the application value of the"five steps four quadrants"modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.METHODS A total of 52 patients who underwent LPD via the"five steps four quadrants"modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively.The patients'body mass index(BMI),preoperative laboratory indices,intraoperative variables and postoperative complications were recorded.The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.RESULTS Among the 52 patients,36 were males and 16 were females,and the average age was 62.2±11.0 years.There were 26 patients with pancreatic head cancer,16 patients with periampullary cancer,and 10 patients with distal bile duct cancer.The BMI was 22.3±3.3 kg/m²,and the median total bilirubin(TBIL)concentration was 57.7(16.0-155.7)µmol/L.All patients successfully underwent the"five steps four quadrants"modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage.Correlation analysis revealed significant associations between preoperative BMI(r=0.3581,P=0.0091),TBIL level(r=0.2988,P=0.0341),prothrombin time(r=0.3018,P=0.0297)and lymph node dissection time.Moreover,dissection time was significantly correlated with intraoperative blood loss(r=0.7744,P<0.0001).Further stratified analysis demonstrated that patients with a preoperative BMI≥21.9 kg/m²and a TIBL concentration≥57.7μmol/L had significantly longer lymph node dissection times(both P<0.05).CONCLUSION The"five steps four quadrants"modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD.This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve;thus,it is worthy of further clinical promotion and application. 展开更多
关键词 Five steps four quadrants Hepatic hilum lymph node Modularized en bloc clearance Laparoscopic pancreaticoduodenectomy
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Stoichiometry and Stability Constant Values for Copper (II) Chelates with Ethylene Diamine in Deep Eutectic Solvents (DES) (Ethaline) Solutions
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作者 Khalid El Ttaib Abdolhadi Benhmid Rifat Hasan Omar 《Open Journal of Applied Sciences》 2024年第9期2592-2609,共18页
In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha... In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values. 展开更多
关键词 CU(II) Ethylene Diamine (en) Deep Eutectic Solvents Job’s Method Ionic Liquids and Stability Constant
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Prolene线在胆总管空肠Roux-en-Y吻合术的临床研究 被引量:2
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作者 唐荣 秦红军 +1 位作者 胡仁健 支春平 《医学信息(中旬刊)》 2010年第4期749-750,共2页
目的:比较Prolene线连续全层缝合与丝线间断全层外翻缝合两种手术方式在胆总管空肠Roux-en-Y吻合术中的优缺点。方法:65例需行胆总管空肠Roux-En-Y吻合术的患者随机分为两组。观察组:30例,行Prolene线连续全层缝合;对照组:35例,行丝线... 目的:比较Prolene线连续全层缝合与丝线间断全层外翻缝合两种手术方式在胆总管空肠Roux-en-Y吻合术中的优缺点。方法:65例需行胆总管空肠Roux-En-Y吻合术的患者随机分为两组。观察组:30例,行Prolene线连续全层缝合;对照组:35例,行丝线间断全层外翻缝合。比较两组间吻合时间、术后感染发生率、吻合口狭窄发生率、胆漏发生率、吻合口出血发生率。结果:观察组的吻合时间、术后感染发生率、吻合口狭窄发生率、胆漏发生率、吻合口出血发生率均著低于对照组(P<O.05)。结论:Prolene线在胆总管空肠Roux-en-Y吻合术中连续全层缝合,操作简单易行,手术时间短,效果良好,且安全可靠,是一种理想的缝合材料和缝合方法。 展开更多
关键词 Prolene线:胆总管 Roux—en—Y吻合术
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氯铝酸离子液体中Glyoxylate-Ene反应合成α-羟基酯 被引量:2
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作者 沈振陆 何锡君 +3 位作者 莫卫民 谢翼 胡宝祥 孙楠 《催化学报》 SCIE EI CAS CSCD 北大核心 2006年第3期197-199,共3页
The chloroaluminate ionic liquid,composed of AlCl3 and 1-butyl-3-methylimidazolium chloride(Cl),is used as the solvent and catalyst to synthesize α-hydroxy esters from alkene and glyoxylate via the glyoxylateene re... The chloroaluminate ionic liquid,composed of AlCl3 and 1-butyl-3-methylimidazolium chloride(Cl),is used as the solvent and catalyst to synthesize α-hydroxy esters from alkene and glyoxylate via the glyoxylateene reaction.Under the reaction conditions of 15 ℃,4 h,and AlCl3/Cl molar ratio of 2,the ethyl α-hydroxy-4-phenyl-4-pentenoate with high yield(95.2%) is obtained in the reaction of α-methyl styrene and ethyl glyoxylate.Other α-hydroxy esters can also be obtained in high yields through the glyoxylate-ene reaction.Moreover,the chloroaluminate ionic liquid can be reused several times. 展开更多
关键词 glyoxylate-ene反应 离子液体 α-羟基酯 氯化铝 乙醛酸酯
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6-yl-hex-1-ene自由基环合成反应机理的理论研究 被引量:1
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作者 于海涛 《黑龙江大学自然科学学报》 CAS 北大核心 2009年第4期516-521,共6页
应用密度泛函理论对6-yl-hex-1-ene自由基环合成反应做了详细的理论研究。通过对随反应坐标变化几个关键变量变化的讨论,揭示了6-yl-hex-1-ene自由基在进行环合成反应时区域选择性的高低;同时,也分析了在6-endo-trig和5-exo-trig反应途... 应用密度泛函理论对6-yl-hex-1-ene自由基环合成反应做了详细的理论研究。通过对随反应坐标变化几个关键变量变化的讨论,揭示了6-yl-hex-1-ene自由基在进行环合成反应时区域选择性的高低;同时,也分析了在6-endo-trig和5-exo-trig反应途径中的热力学和动力学势垒的变化,以及六元环产物和五元环产物的环张力对热力学过程和动力学过程可能产生的影响。结果表明在6-yl-hex-1-ene自由基环合成过程中,经过5-exo-trig反应途径生成环应力较大的五元环产物具有动力学优势,是主要的动力学产物。同时分析结果也表明,可以利用在反应过程中进攻角变量的变化来定性地判断反应选择性的优势通道,并用以定性地解释Baldwin规则的结论。 展开更多
关键词 反应机理 6-yl—hex-1-ene自由基 密度函数理论 自由基环合成
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烯烃与单重态氧的“ene”反应
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作者 柳湘云 姜淑芳 《哈尔滨师范大学自然科学学报》 1995年第1期52-58,共7页
本文以数学研究为基础,系统研究综述有机物光氧化反应的重要基础理论─烯烃与单重态氧(1△g态1O2)的“ene”反应,论述它的典型反应、反应特性、反应机理及其在有机合成上的应用。
关键词 烯烃 单重态 氧分子 ene反应 光氧化反应
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铜络合物手性催化羰基ene反应的密度泛函研究
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作者 孟庆喜 《山东化工》 CAS 2017年第1期8-10,共3页
应用密度泛函理论在M06/6-31G(d,p)(对铜应用LANL2DZ(f)基组)水平下细研究了手性噁唑啉铜(Ⅱ)催化二酮酯与烯烃的不对称羰基ene反应。该反应有四条可能反应通道,主要经历了噁唑啉铜(Ⅱ)与二酮酯配位生成络合物m1,络合物m2a1、m2a2、m2b1... 应用密度泛函理论在M06/6-31G(d,p)(对铜应用LANL2DZ(f)基组)水平下细研究了手性噁唑啉铜(Ⅱ)催化二酮酯与烯烃的不对称羰基ene反应。该反应有四条可能反应通道,主要经历了噁唑啉铜(Ⅱ)与二酮酯配位生成络合物m1,络合物m2a1、m2a2、m2b1、m2b2,噁唑啉铜-α-羟基-β-酮酯络合物m3a、m3b。烯烃进攻噁唑啉铜-二酮酯络合物m1是手性噁唑啉铜(Ⅱ)催化二酮酯与烯烃的不对称羰基ene反应的速率决定步骤,也是该反应的手性决定步骤。因此该反应的主要反应通道为:m1→TS_(m1-m2a1)→m2a1→TS_(m2a1-m3a)→m3a,主要产物为(S)-α-羟基-β-酮酯,这与M.P.Doyle课题组的实验研究一致。 展开更多
关键词 铜络合物 羰基ene反应 2 3-二酮酯 密度泛函理论
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5-yl-pent-1-ene自由基环合成反应机理的理论研究
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作者 于海涛 赵艳丽 仲华 《黑龙江大学自然科学学报》 CAS 北大核心 2009年第5期666-670,共5页
应用密度泛函理论对5-yl-pent-1-ene自由基环合成反应做了详细的理论研究。结果表明,反应经4-exo-trig过程生成四元环产物是一个吸热反应,而经5-endo-trig过程则是一个放热反应,说明在热力学上5-endo-trig过程比4-exo-trig过程有利。环... 应用密度泛函理论对5-yl-pent-1-ene自由基环合成反应做了详细的理论研究。结果表明,反应经4-exo-trig过程生成四元环产物是一个吸热反应,而经5-endo-trig过程则是一个放热反应,说明在热力学上5-endo-trig过程比4-exo-trig过程有利。环张力的计算结果说明四元环较大的环张力是形成四元环过程需要吸热的一个主要原因,而五元环较小的环张力是反应放热的一个原因。从动力学势垒来看,5-endo-trig反应过程也比4-exo-trig过程稍微有利,这是违反Baldwin规则的。这是由于自由基环合成所形成的四元环张力要比五元环张力大所引起的,因此环张力是在四元环形成过程中动力学上需要克服的主要障碍之一,也是导致其动力学势垒较高的主因。五元环产物的势垒主要是由于进攻角度变化较大而引起的。因此,Baldwin规则中进攻角度决定环合成反应选择性的理论不适用于5-yl-pent-1-ene自由基环合成过程。 展开更多
关键词 反应机理 5-yl-pent-1-ene自由基 密度函数理论 自由基环合成
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Lewis酸催化Glyoxylate-Ene反应合成α-羟基酯的研究
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作者 何锡君 沈振陆 +3 位作者 莫卫民 谢翼 胡宝祥 孙楠 《化学世界》 CAS CSCD 北大核心 2006年第12期740-742,745,共4页
研究比较了几种Lewis酸对α-甲基苯乙烯和乙醛酸乙酯反应合成α-羟基-4-苯基-4-戊烯酸乙酯(EHPP)的催化性能,其中SnCl4的催化活性最高。在n(α-甲基苯乙烯)∶n(乙醛酸乙酯)∶n(SnCl4)=1∶1∶0.03,反应温度20℃,反应时间90 min的条件下,... 研究比较了几种Lewis酸对α-甲基苯乙烯和乙醛酸乙酯反应合成α-羟基-4-苯基-4-戊烯酸乙酯(EHPP)的催化性能,其中SnCl4的催化活性最高。在n(α-甲基苯乙烯)∶n(乙醛酸乙酯)∶n(SnCl4)=1∶1∶0.03,反应温度20℃,反应时间90 min的条件下,α-甲基苯乙烯的转化率为98.6%,EHPP的选择性和收率分别达到95.6%和94.3%。同时研究了其他烯烃和乙醛酸酯合成α-羟基酯的反应,结果表明SnCl4也具有较高的催化活性。 展开更多
关键词 Glyoxylate—ene反应 α-羟基酯 乙醛酸乙酯 Α-甲基苯乙烯 催化 SNCL4
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Extension of e^N method to general three-dimensional boundary layers 被引量:4
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作者 Lei ZHAO Gaotong YU Jisheng LUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第7期1007-1018,共12页
In order to extend the eN method to general three-dimensional boundary layers, the conservation law of the imaginary parts for the wave parameters with a fixed wave vector is deduced. The compatibility relationship ... In order to extend the eN method to general three-dimensional boundary layers, the conservation law of the imaginary parts for the wave parameters with a fixed wave vector is deduced. The compatibility relationship (CR) and the general theory of ray tracing (RT), which have been extensively used in conservative systems, are applied to a general three-dimensional boundary layer belonging to non-conservative systems. Two kinds of eN methods, i.e., the eN-CR method and the eN-RT method, are established. Both the two kinds of methods can wavenumber and the amplitude of the be used to predict the evolutions of the spanwise disturbances in general three-dimensional boundary layers. The reliability of the proposed methods is verified and validated by performing a direct numerical simulation (DNS) in a hypersonic general three-dimensional boundary layer over an aircraft model. The results are also compared with those obtained by other eN methods, indicating that the proposed methods have great potential applications in improving the transition prediction accuracy in general three-dimensional boundary layers. 展开更多
关键词 eN method ray tracing theory transition prediction three-dimensionalboundary layer
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Effectiveness of circumferential endoscopic mucosal resection with a novel tissue-anchoring device 被引量:3
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作者 Yunho Jung Masayuki Kato +3 位作者 Jongchan Lee Mark A Gromski Ram Chuttani Kai Matthes 《World Journal of Gastrointestinal Endoscopy》 CAS 2013年第6期275-280,共6页
AIM: To evaluate the efficacy of circumferential endoscopic mucosal resection (EMR) with a tissue-anchoring device in comparison to forceps precut EMR and conventional endoscopic submucosal dissection (ESD). METHODS: ... AIM: To evaluate the efficacy of circumferential endoscopic mucosal resection (EMR) with a tissue-anchoring device in comparison to forceps precut EMR and conventional endoscopic submucosal dissection (ESD). METHODS: The study was designed as a prospective, randomized, ex vivo study. Fresh ex vivo specimens were harvested from adult white Yorkshire pigs weighing 30-50 kg. Seventy-five standardized, artificial lesions measuring 3 cm × 3 cm were created by methy- lene blue tattoo at the greater curvature in fresh ex vivo stomachs using the EASIE-R simulator platform (Endosim LLC, Berlin, MA, United States). The three advanced endoscopists performed the three resection techniques such as circumferential EMR using the tissue-anchoring device (TA-EMR), forceps precut EMR (FP-EMR), and endoscopic submucosal dissection. The endoscopists and the type of cutting methods were determined randomly by grouped randomized selection.The resection bed was grossly inspected to determine whether the lesion was resected "en-bloc " (defined as no remaining mucosal tattoo remaining on specimen). The resection bed was also probed for evidence of perforation. The procedural time of circumferential resection, submucosal dissection, and injection frequency were recorded by an independent observer.RESULTS: All 75 created lesions were successfully resected by three advanced endoscopists using the three techniques. The mean ± SD size of resected specimens (long axis) were 39.5 ± 5.6 mm, 36.5 ± 7.3 mm, and 44.6 ± 5.6 mm for TA-EMR, FP-EMR, and ESD respectively. The overall mean dissection time of both the TA- EMR and FP-EMR was significant shorter than ESD (TA- EMR: 5.1 ± 3.3 min, FP-EMR: 3.5 ± 2.0 min vs ESD: 15.8 ± 9.5 min, P < 0.001, P < 0.001). The overall mean total procedure time of both the tissue-anchoring and forceps circumferential EMR was significantly shorter than ESD (TA-EMR: 17.5 ± 6.0 min, FP-EMR: 16.6 ± 6.6 min vs ESD: 28.6 ± 13.9 min, P < 0.001, P < 0.001). The en-bloc resection rate of ESD was 100% (25/25) and the en-bloc resection rate of the TA-EMR (84.0%, 21/25) was higher than for the FP-EMR (60.0%, 15/25), yet not statistically significant (P = 0.18). The perforation rate of each technique was 8.0% (2/25). CONCLUSION: TA-EMR appears to be quicker than ESD, and there was a trend towards improved en bloc resection rate with the TA-EMR when compared to the FP-EMR. 展开更多
关键词 ENDOSCOPIC MUCOSAL RESECTION ENDOSCOPIC SUBMUCOSAL dissection En bloc RESECTION PERFORATION
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Chemistry and health beneficial effects of oolong tea and theasinensins 被引量:10
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作者 Monthana Weerawatanakorn Wei-Lun Hung +4 位作者 Min-Hsiung Pan Shiming Li Daxiang Li Xiaochun Chi-Tang Ho 《Food Science and Human Wellness》 SCIE 2015年第4期133-146,共14页
Among six major types of tea(white,green,oolong,yellow,black,and dark teas)from Camellia sinensis,oolong tea,a semi-fermented tea,with its own unique aroma and taste,has become a popular consumption as indicated by th... Among six major types of tea(white,green,oolong,yellow,black,and dark teas)from Camellia sinensis,oolong tea,a semi-fermented tea,with its own unique aroma and taste,has become a popular consumption as indicated by the increasing production.Representing the characteristic flavonoids of oolong tea,theasinensins are dimeric flavan-3-ols.Many recent studies have indicated that oolong tea and theasinensins possess several health benefit properties.We consider it significant and necessary to have a comprehensive review in the recent advances of oolong tea.Therefore,the aim of the present review is to provide a new perspective on oolong tea and its characteristic phytochemicals,theasinensins associated with health benefits,molecular action pathway,and chemical mechanism of theasinensin formation from scientific evidences available on the literature.Furthermore,the chemical characterization of the oxidation products and the model oxidation system to the chemical changes of theasinensins are also discussed. 展开更多
关键词 properties. ens INS
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Dual loop(Roux en Y) reconstruction with isolated gastric limb reduces delayed gastric emptying after pancreatico-duodenectomy 被引量:1
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作者 Offir Ben-Ishay Reem Abu Zhaya Yoram Kluger 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2019年第2期93-100,共8页
BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstr... BACKGROUND Single loop reconstruction(SLR) was routine in our institution for patients undergoing pancreatico-duodenectomy(PD). Roux-en Y reconstruction with an isolated gastric limb(RIGL) recently became the reconstruction of choice.AIM To evaluate the impact of RIGL on incidence and severity of delayed gastric emptying(DGE).METHODS This is a single institution, retrospective analysis of patients undergoing PD. All patients undergoing PD from July 2010 through December 2016 were included in the study. Outcome of RIGL were compared to SLR. Primary measure of outcome included incidence and severity of DGE. Secondary measures of outcome were overall complications and postoperative mortality.RESULTS One hundred and seventy-nine patients were included in the study. Fifty-two had RIGL, 127 had SLR. Overall complication rate was 40.2%, patients in the RIGL group experienced lower rates of DGE(15.4% vs 59.1%, P = 0.001). Other patient related outcomes were also significantly reduced: day of nasogastric tube removal(3 vs 5, P < 0.001), regain of normal diet(8 vs 9, P < 0.001). On multivariate analysis RIGL was associated independently with reduced rates of DGE(P < 0.001, OR 0.14)CONCLUSION The current study shows that RIGL reduces the rate of DGE after PD. Further prospective randomized controlled trials are required to affirm the current data. 展开更多
关键词 PANCREATICODUODeneCTOMY Delayed GASTRIC EMPTYING Complications ROUX EN Y
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Progress and prospects of innovative coal-fired power plants within the energy internet 被引量:7
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作者 Yongping Yang Chengzhou Li +1 位作者 Ningling Wang Zhiping Yang 《Global Energy Interconnection》 2019年第2期160-179,共20页
The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy ... The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy internet. Progressive penetration of intermittent renewable energy sources into the energy system has led to unprecedented challenges to the currently wide use of coal-fired power generation technologies. Here, the applications and prospects of advanced coal-fired power generation technologies are analyzed. These technologies can be summarized into three categories:(1) large-scale and higher parameters coal-fired power generation technologies, including 620/650/700 oC ultra-supercritical thermal power and double reheat ultra-supercritical coal-fired power generation technologies;(2) system innovation and specific, highefficiency thermal cycles, which consist of renewable energy-aided coal-fired power generation technologies, a supercritical CO_2 Brayton cycle for coal-fired power plants, large-scale air-cooling coal-fired power plant technologies, and innovative layouts for waste heat utilization and enhanced energy cascade utilization;(3) coal-fired power generation combined with poly-generation technologies, which are represented by integrated gasification combined cycle(IGCC) and integrated gasification fuel cell(IGFC) technologies. Concerning the existing coal-fired power units, which are responsible for peak shaving, possible strategies for enhancing flexibility and operational stability are discussed. Furthermore, future trends for coal-fired power plants coupled with cyber-physical system(CPS) technologies are introduced. The development of advanced, coal-fired power generation technologies demonstrates the progress of science and is suitable for the sustainable development of human society. 展开更多
关键词 En ergy In ternet Coal-fired POWER GEN eration FLEXIBILITY Cyber-physical system Smart POWER plant
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Temperature-Dependent Far-Infrared Absorption in Cyclotrimethylene Trinitramine Single Crystals Using Broadband Time-Domain Terahertz Spectroscopy 被引量:1
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作者 Yupeng Liu Jinchun Shi Chongyang Chen 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第1期46-50,共5页
We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit str... We investigate the absorption properties of cyclotrimethylene trinitramine(RDX) single crystals from ~15 to150 cm^(-1) using the terahertz time-domain spectroscopy. We observe that all the absorption modes exhibit strong anisotropic behavior in terms of the crystal orientations. We demonstrate that the anharmonic phonon model can well describe the temperature-dependent behaviors of these absorption modes. These results indicate that the intermolecular interaction plays a major role in the collective motion of large number of RDX molecules. Our findings provide important information for understanding and controlling the dynamic properties in the explosive materials. 展开更多
关键词 spectroscopy ene ABSORPTION
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Distribution of Welding Residual Stress of Mixed Steel U-Rib-Stiffened Plates 被引量:4
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作者 Qiu Zhao Zhansheng Zhai Yu Nie 《Transactions of Tianjin University》 EI CAS 2018年第5期489-500,共12页
To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress ... To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress was calculated using a simplified calculation method. The method involved welding the mixed steel U-rib-stiffened plates for a structure with different sizes and different strength ratios of U-rib to plate. Based on a welding residual stress numerical simulation method validated by the blind hole method test, the distribution law of the mixed steel U-rib stiffened plate was studied. The results showed that the change of plate width has little impact on the welding residual stress and that the ratio of the thicknesses of the plate to U-rib stiffeners, the thickness of the plate, and the thickness of the U-rib has a great influence on the distribution of the welding residual stress. The thickness of plate and steel strength also greatly influenced the distribution width of the residual tensile stress. While analyzing the compression capacity of U-rib-stiffened plates, the simplified distribution of welding residual stress was used. 展开更多
关键词 STEEL bridge Welding RESIDUAL stress Simplifi ed calculation METHOD U-rib STIFF ened plate Finite element METHOD
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Two New Pentacyclic Triterpenes from Sabia parviflora 被引量:15
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作者 Jin CHEN Bin CHEN +1 位作者 Jun TIAN Feng E WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期345-348,共4页
Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.
关键词 Sabia parviflora pentacyclic triterpene acid 3b-dihydroxyl-olean-12-en-28-oic acid 1a 2a 3b-trihydroxyl-olean-12-en-28-oic acid.
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Identification of salinity-related genes in ENO2 mutant (eno2~–) of Arabidopsis thaliana 被引量:1
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作者 ZHANG Yong-hua CHEN Chao +6 位作者 SHI Zi-han CHENG Hui-mei BING Jie MA Xiao-feng ZHENGChao-xing LI Hong-jie ZHANG Gen-fa 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第1期94-110,共17页
Abiotic stress poses a great threat to plant growth and can lead to huge losses in yield. Gene enolase2 (EN02) is important in resistance to abiotic stress in various organisms. ENO2 T-DNA insertion mutant (enoZ) ... Abiotic stress poses a great threat to plant growth and can lead to huge losses in yield. Gene enolase2 (EN02) is important in resistance to abiotic stress in various organisms. ENO2 T-DNA insertion mutant (enoZ) plants of Arabidopsis thaliana showed complete susceptibility to sodium chloride treatment when were analyzed either as whole plants or by measuring root growth during NaCl treatment. Quantitative real-time RT-PCR (RT-qPCR) was performed to investigate the expression profile of EN02 in response to NaCl stress in Arabidopsis. The transcript level of EN02 was rapidly elevated in 300 mmol L-1 NaCl treatment. ENO2 also responded to 300 mmol L 1 NaCl treatment at the protein level. To illuminate the mechanism underlying EN02 resistance to salt at the transcriptional level, we studied the wild-type and enoZ Arabidopsis lines that were treated with 300 mmol L 1 NaCl for 18 h using 454 GS FLX, which resulted in an expressed sequence tag (EST) dataset. A total of 961 up-regulated and 746 down-regulated differentially expressed genes (DEGs) were identified in the pairwise comparison w-r-18 h:eno2^-18 h. The DEGs were identified and functionally annotated using the databases of Gene Ontology (GO) and the Kyoto encyclopedia of genes and genomes (KEGG). The identified unigenes were subjected to GO analysis to determine biological, molecular, and cellular functions. The biological process was enriched in a total of 20 GO terms, the cellular component was enriched in 13 GO terms, and the molecular function was enriched in 11 GO terms. Using KEGG mapping, DEGs with pathway annotations contributed to 115 pathways. The top 3 pathways based on a statistical analysis were biosynthesis of the secondary metabolites (KO01110), plant-pathogen interactions (KO04626), and plant hormone signal transduction (KO04075). Based on these results, EN02 contributes to increased resistance to abiotic stress. In particular, EN02 is involved in some of the metabolic stress response pathways in Arabidopsis. Our work also demonstrates that this EST dataset will be a powerful resource for further studies of EN02, such as functional analyses, investigations of biological roles, and molecular breeding. Additionally, 3-phosphoglycerate kinase (PGK), 3-phosphoglycerate kinase 1 (PGK1), triosephosphate isomerase (TPI), and pyruvate kinase (PK) in glycolysis interactions with ENO2 were verified using the yeast two-hybrid experiment, and EN02 may regulate the expression of PGK, PGK1, TPI, and PK. Taken together, the results from this study reflects that EN02 gene has an important role in the response to the high salt stress. 展开更多
关键词 EN02 NaCI tolerance abiotic stress 454 GS FLX sequencing GO KEGG
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New Triterpenes from Siyekucai (Ixeris chinensis) 被引量:13
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作者 Shu Jun ZHANG Jin Lan WANG +1 位作者 Qi Gang DENG Masayoshi ANDO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第2期195-197,共3页
Three new triterpenes, 3β,21α-dihydroxylupen-18(19)-en (1), 3β,25-dihydroxytirucalla- 7,23(24)-dien (2), and 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en (3) were obtained from an ethyl acetate extr... Three new triterpenes, 3β,21α-dihydroxylupen-18(19)-en (1), 3β,25-dihydroxytirucalla- 7,23(24)-dien (2), and 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en (3) were obtained from an ethyl acetate extract of the whole plant of Siyekucai (Ixeris chinensis). The structures of 1-3 were determined by spectroscopic methods (EIMS, IR, 1D and 2D NMR). 展开更多
关键词 Ixeris chinensis trierpene 21α-dihydroxylupen-18(19)-en (1) 25-dihydroxy-tirucalla-7 23(24)-dien 21α-hydroxy-19α-hydrogentaraxastero1-20(30)-en.
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Thermodynamics of solubility of Cu_2(OH)_2CO_3 in ammonia-ammonium chloride-ethylenediamine(En)-water system 被引量:2
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作者 刘维 唐谟堂 +3 位作者 唐朝波 何静 杨声海 杨建广 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第2期336-343,共8页
In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.... In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process. 展开更多
关键词 thermodynamics solubility malachite ammonia ammonium chloride ethylenediamine(En)
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