检索结果-南通市图书馆

Laboratory study of the formation of fullerene(from smaller to larger, C44 to C70)/anthracene cluster cations in the gas phase

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2020年第12期20卷 299-306页

作者： De-Ping Zhang Yuan-Yuan Yang Xiao-Yi Hu jun-feng zhen CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics Hefei National Laboratory for Physical Sciences at the Microscaleand Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China

The formation and evolution mechanism of fullerenes in the planetary nebula or in the interstellar medium are still not ***,we present the study on the cluster formation and the relative reactivity of fullerene cations(from smaller to larger,C44 to C70) with anthracene molecule(C14H10).The experiment is performed in an apparatus that combines a quadrupole ion trap with a time-of-flight mass *** using a 355 nm laser beam to irradiate the trapped fullerenes cations(C60+or C70+),smaller fullerene cations C(60-2 n)+, n=1-8 or C(70-2 m)+,m=1-11 are generated,*** reacting with anthracene molecules,series of fullerene/anthracene cluster cations are newly formed(e.g.,(C14H10)C(60-2 n)+,n=1-8 and(C14H10)C(70-2 m)+,m=1-11),and slight difference of the reactivity within the smaller fullerene cations are ***,smaller fullerenes show obviously higher reactivity when comparing to fullerene C60+ and C70+.A successive loss of C2 fragments mechanism is suggested to account for the formation of smaller fullerene cations,which then undergo addition reaction with anthracene molecules to form the fullerene-anthracene cluster *** is found that the higher laser energy and longer irradiation time are key factors that affect the formation of smaller fullerene *** may indicate that in the strong radiation field environment(such as photon-dominated regions) in space,fullerenes are expected to follow the top-down evolution route,and then form small grain dust(e.g.,clusters) through collision reaction with co-existing molecules,here,smaller PAHs.

关键词： astrochemistry methods:laboratory ultraviolet:ISM ISM:molecules molecular processes

Laser-induced Fluorescence Excitation Spectrum of NiS in 15500-17200 cm^-1

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2009年第6期22卷 668-672,J0002,I0003页

作者： jun-feng zhen Li Wang Cheng-bing Qin Qun Zhang Yang Che Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of China Hefei 230025 China

The laser-induced fluorescence excitation spectrum of jet-cooled NiS molecule has been recorded in the energy range of 15500 17200 cm-1. Fifteen bands have been assigned as three transition progressions：[15.65]^3Ⅱ1（v′=0-4）-X^3∑0^-（v″=0）,[15.69]^3∑0^-（v′=0-4）-X^3∑0^-（v″=0）,and [15.81]^3Ⅱ1（v′=0-4）-X^3∑0^-（v″=0）.Spectroscopic constants for the three newly identified electronically excited states have been determined for the first time. In addition,the lifetimes for most observed vibronic bands have also been measured.

关键词： NiS Laser-induced fluorescence spectrum DC discharge

Modulation of TGFβ_2 and dopamine by PKC in retinal Müller cells of guinea pig myopic eye

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2011年第4期4卷 357-360页

作者： jun-feng Mao, Shuang-zhen Liu, Wen-Juan Qin, Qian Xiang Department of Ophthalmology, Xiangya Hospital of Central South University, Changsha 410008, Hunan Province, China Department of Ophthalmology Xiangya Hospital of Central South University Changsha 410008 Hunan Province China

AIM: To investigate the effect of protein kinase C (PKC) on transforming growth factor-β2 (TGFβ2) and dopamine in retinal Müller cells of guinea pig myopic eye. METHODS: Myopia was induced by translucent goggles in guinea pig, whose retinal Müller cells were cultured using the enzyme-digesting method. Retinal Müller cells were divided into 5 groups: normal control, myopia, myopia plus GF109203X, myopia plus PMA, myopia plus DMSO. PKC activities were detected by the non-radioactive methods. TGFβ2 and tyrosine hydroxylase (TH) proteins were analyzed by Western Blotting in retinal Müller cells. Dopamine was determined by the high-performance liquid chromatography- electrochemical detection in suspensions. RESULTS: After 14 days deprived, the occluded eyes became myopic with ocular axle elongating. Müller cells of guinea pigs were obtained using enzyme digestion. Compared with normal control group, the increase in PKC activity and the up-regulation in TGFβ2 expression were found in retinal Müller cells of myopic eyes, with the decrease of TH and dopamine content (P <0.05). After PKC activated by PMA, TGFβ2 and TH content were up-regulated with the increase of dopamine content (P <0.05). While the PKC activities was inhibited by GF109203X, proteins of TGFβ2 and TH were down-regulated in the myopic eyes, with the decrease of dopamine content (P <0.05). CONCLUSION: TGFβ2 and dopamine are modulated by PKC in Müller cells of the myopic eyes in guinea pig.

关键词： protein kinase C retinal Müller cell transforming growth factor-β2 dopamine myopia

Research of Dynamic Material Handling in an Automobile General Assembly Line Based on Real-time Information

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Plant Engineering and Management 2012年第1期17卷 34-43页

作者： WANG Nan LI Shi-qi WANG jun-feng ZHANG zhen-li School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

The status of material delivery of an automobile general assembly line is analyzed, and the technique to achieve the real-time tracking of assembly status information is proposed based on RFID（ Radio Frequency Identification）. Thus the consumption of line-side buffer is obtained dynamically, then the type and quantity of needed material are fed back to the subsystem of material handling; the algorithm for determining the best time departure time of delivery driver based on minimizing of total time penalty function is proposed. This approach makes the material amount of a single delivery trip maximized and improves the efficiency of delivery drivers significantly in the case of does not affect the assembly line normal throughput. Additionally, although this dynamic material handling method is developed for the automobile assembly plant, it should be pointed out that this method is also applicable to other mixed model assembly plants such as electronics, semiconductor and aerospace industry.

关键词： automobile general assembly line material handling best departure time

Experimental Determination of the Vibrational Constants of FeS（X5 △） by Dispersed Fluorescence Spectroscopy

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2011年第1期24卷 1-3,I0003页

作者：王莉黄道菱甄军锋张群陈旸中国科学技术大学合肥微尺度物质科学国家实验室化学物理系合肥230026

Based on previous laser-induced fluorescence excitation spectroscopy work, the vibrational constants of neutral FeS in the X5 △ electronic state were obtained by directly mapping the ground-state vibrational levels up to v＂=3 using conventional laser-induced dispersed fluorescence spectroscopy. The vibrational frequency of FeS（X5 △）（518±5 cm-1） agrees well with that reported in a recent PES measurement （520±30 cm-1） [J. Phys. Chem. A 107, 2821 （2003）] which is the only one prior experimental vibrational frequency value for the 5 △ state of FeS. Careful comparisons of our experimental results and those documented in the literature （mainly from theoretical predictions） suggest that the ground state of FeS is 5 △ state.

关键词： FeS Vibrational constant Laser-induced dispersed fluorescence spectroscopy

Laser-induced Fluorescence and Dispersed Fluorescence Spectroscopy of NiB： Identification of a New 2П State in 19000-22100 cm^-1

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2010年第6期23卷 626-629,745页

作者：甄军峰王莉秦成兵张群陈旸中国科学技术大学合理微尺度物质科学国家实验室化学物理系合肥230026

The laser-induced fluorescence excitation spectra of jet-cooled NiB radicals have been recorded in the energy range of 19000-22100 cm-1. Eleven bands have been assigned to the [20.77]2П-X2∑＋ transition system for the first time. The dispersed fluorescence spectra related to most of these bands have been investigated. Vibrationally excited levels of the ground electronic state, with v＂ up to 6, have been observed. In addition, the lifetimes for almost all the observed bands have also been measured.

关键词： NiB Laser-induced fluorescence Dispersed fluorescence Direct cm'rent discharge

Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2025年第1期17卷 143-157页

作者： Xian-Rang Cao Yin-Long Xu Jia-Wei Chai Kai zheng jun-Jie Kong jun Liu Shun-zhen zheng Department of Liver Transplantation and Hepatobiliary Surgery Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina Department of Breast and Thyroid Surgery Shandong Provincial Maternal and Child Health Care HospitalJinan 250014Shandong ProvinceChina

BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various *** To explore the association between pretreatment RDW and short-term outcomes after laparoscopic pancreatoduodenectomy(LPD).METHODS A total of 804 consecutive patients who underwent LPD at our hospital between March 2017 and November 2021 were retrospectively *** between pretreatment RDW and clinicopathological characteristics and short-term outcomes were *** Patients with higher pretreatment RDW were older,had higher Eastern Cooperative Oncology Group scores and were associated with poorer short-term outcomes than those with normal *** pretreatment RDW was an independent risk factor for postoperative complications(POCs)(hazard ratio=2.973,95%confidence interval:2.032-4.350,P<0.001)and severe POCs of grade IIIa or higher(hazard ratio=3.138,95%confidence interval:2.042-4.824,P<0.001)based on the Clavien-Dino classification *** analysis showed that high pretreatment RDW was an independent risk factor for Clavien-Dino classi-fication grade IIIb or higher POCs,a comprehensive complication index score≥26.2,severe postoperative pancreatic fistula,severe bile leakage and severe *** pretreatment RDW was positively associated with the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio and was negatively associated with albumin and the prognostic nutritional *** Pretreatment RDW was a special parameter for patients who underwent *** was associated with malnutrition,severe inflammatory status and poorer short-term *** could be a surrogate marker for nutritional and inflammatory status in identifying patients who were at high risk of developing POCs after LPD.

关键词： Biomarker Laparoscopic pancreatoduodenectomy Postoperative complication Red blood cell distribution width Short-term outcomes

华北东濮凹陷沙河街组藻类化石所记录的地质事件

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

微体古生物学报 2002年第3期19卷 316-321页

作者：范迎风顾勤黄俊峰高渐珍中石化集团中原油田分公司勘探开发科学研究院河南457001

东濮凹陷早第三纪沙河街组产有丰富的藻类化石 ,淡水藻类与半咸水、咸水藻类相互交替的两个旋回在纵向上分布明显 ,即 :沙四、沙二段为淡水藻类 (主要为轮藻 )发育期 ,沙三、沙一段为咸水、半咸水藻类 (主要为沟鞭藻 )发育期。根据藻类... 详细信息

东濮凹陷早第三纪沙河街组产有丰富的藻类化石 ,淡水藻类与半咸水、咸水藻类相互交替的两个旋回在纵向上分布明显 ,即 :沙四、沙二段为淡水藻类 (主要为轮藻 )发育期 ,沙三、沙一段为咸水、半咸水藻类 (主要为沟鞭藻 )发育期。根据藻类化石的生态分析 ,认为沙三、沙一段沉积期湖水的咸化事件是由海侵造成的。

关键词：华北东濮凹陷沙河街组藻类化石地质事件古生态

Expression Cox-2 Protein in Gastric Carcinoma and Paracancerous Tissues

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

胃肠病学 2000年第B8期5卷 148-148页

作者： GaoHeng-jun BaiJian-feng YuLian-zhen LvXiu-zhen ZhangXiao-yong ZhaoZhi-quan Dept.ofGastroenterology TheFirstAffiliatedHospitalofNanjingMedicalUniversityNanjing210029China