检索结果-南通市图书馆

Photodissociation Dynamics of Methanol and Ethanol at 157 nm

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2008年第4期21卷 301-307页

作者： Kai-jun Yuan Yuan Cheng feng-yan wang Xue-ming yang State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 116023 China

157 nm photodissociation of jet-cooled CH3OH and C2HsOH was studied using the high-n Rydberg atom time-of-flight （TOF） technique. TOF spectra of nascent H atom products were measured. Simulation of these spectra reveals three different atomic H loss processes： one from hydroxyl H elimination, one from methyl （ethyl） H elimination, and one from secondary dissociation of the methoxy （ethoxy） radical. The relative branching ratio indicates secondary dissociation of ethoxy is less important than that of methoxy. The average angular anisotropy parameter of methanol is negative （with β≈-0.3）, indicating the transition dipole moment is perpendicular to the C-O-H plane. The slightly more negative β value of ethanol （with β≈-0.4） implies that ethanol has a longer rotational period. These experimental results indicate that both systems undergo fast internal conversion to the 3s surface after it is excited to the 3px surface, and then dissociate on the 3s surface. The translational energy distribution of the CH3O＋H products reveals extensive CH3 rocking or CH3 umbrella excitation in the CH30 radical. However the vibrational structures are not resolved in the C2H5O radical.

关键词： Photodissociation dynamics H atom channel VUV photolysis

A Velocity Map Ion-imaging Study on Ketene Photodissociation at 218 nm

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 2006年第1期19卷 1-5页

作者： Jie Liu feng-yan wang Hua wang Bo Jiang Xue-ming yang State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 116023 China

Photodissociation dynamics of ketene at 218 nm has been investigated using the velocity map ion-imaging method. Both angular and translational energy distributions for the CO products at different rotational and vibrational states have been obtained. The 2＋1 REMPI spectrum of CO products is also obtained. The results are as bellow：（i） CO products in the first two vibrational states （ v＂=0 and v＂=1 ） exhibit significant rotational excitation. Furthermore the rotational excitation of CO at the v＂=0 level is noticeably higher than that at the v＂=1 level. （ii） It was found that the major photodissociation pathway of ketene at 218 nm is the CH2（ǎ^1A1）＋CO（X^1∑^＋） channel, while the CH2（b^1B1）＋CO（X^1∑^＋） channel and the CH2（X^3B1）＋CO（X^1E^＋） channel are also likely present, （iii） The anisotropy parameters β of CO different rovibronic states all appear to be larger than zero. No significant difference is observed at the two vibrational states,

关键词： Velocity map ion-imaging Photodissociation Anisotropy parameter Translational energy distribution

CGI-100 Specific shRNA Inhibits Proliferation and Induces Differentiation in Leukemia K562 Cells

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Cancer Research 2010年第2期22卷 126-134页

作者： Yong-qiang wang Ting-mei Chen yan Lei Hong-lei feng Ke wang yan Zhang The Key Laboratory of Laboratory Medical Diagnostics of Ministry of Education Department of Clinical Biochemistry Chongqing Medical University Chongqing 400016 China

Objective： To investigate the characteristics of CGI-100- knockdown K562 cells and the effect of CGI-100 RNA interference （RNAi） on matrine-treated K562 cells. Methods： Three oligonucleotides targeting CGI-100 gene and a pair of negative control containing the same nucleotide composition with a different sequence were devised and chemically synthesized. The inhibition efficiency of CGI-100 expression by shRNA-CGI-100 in K562 cells was determined using semiquantitative RT-PCR and dot blot hybridization. The effect of CGI-100 RNAi on the growth of K562 cells was examined using MTT assay and cell differentiation was measured by distinct approaches including flow cytometry, benzidine staining and electron microscope. After CGI-100-konckdown K562 cells were incubated with 0.2 mg/ml of matrine or 30 Ixmol/L of hemin for 48 h, the expression levels of Glycophorin A（GPA）（CD235a） and Growth factor independence-lB mRNA（Gfi-IB mRNA） were measured by RT-PCR and the protein levels of GPA, CD14 and CD15 were detected by flow cytometry. Results： The eukaryotic expression vectors of CGI-100 RNAi were successfully constructed. The K562/shRNA-CGI-100 cell line was established in which the inhibition efficiency of CGI-100 gene expression by shRNA-CGI-100 was 54%. CGI-100-knockdown inhibited the proliferation and induced erythroid differentiation in K562 cells. Compared with the control K562 cells, the K562/shRNA-CGI-100 cells showed decreased absorbance value detected by MTT assay, decreased enchromation, increased heterochromation, increased percentage of G0/Gx phase cells, decreased population of S phase cells, decreased PI （proliferation index of cells）, and elevated percentage of benzidine-positive cells. Moreover, the sensitivity of K562/shRNA-CGI-100 cells to either matrine or hemin was enhanced and the sensitivity of these cells to matrine was higher than that to hemin. Compared with the control K562 cells, matrine treatment in K562/shRNA-CGI-100 cells resulted in increased i

关键词： CGI-100 RNA interference Leukemia Erythroid differentiation Matrine

UV Photodissociation Dynamics of Nitric Acid： The Hydroxyl Elimination Channel

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2期22卷 191-196页

作者： feng-yan wang Zhi-chao Chen Yong-wei Zhang Quan Shuai Bo Jiang Dong-xu Dai Xiu-yan wang Xue-ming yang State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Sliced velocity mapping ion imaging technique was employed to investigate the dynamics of the hydroxyl elimination channel in the photodissociaiton of nitric acid in the ultraviolet region. The OH product was detected by （2＋1） resonance enhanced multiphoton ionization via the D^2∑^- electronic state. The total kinetic energy spectra of the OH＋NO2 channel from the photolysis of HONO2 show that both ：NO2（X2A1） and NO2（A2B2） channels are present, suggesting that both 1^1A″ and 2^1A″ excited electronic states of HONO2 are involved in the excitation. The parallel angular distributions suggest that the dissociation of the nitric acid is a fast process in comparison with the rotational period of the HNO3 molecule. The anisotropy parameter β for the hydroxyl elimination channel is found to be dependent on the OH product rotational state as well as the photolysis energy.

关键词： Slice imaging technique Photodissociation dynamics Nitric acid OH radical Resonance enhanced multiphoton ionization

Expression of OCT4 in human esophageal squamous cell carcinoma is significantly associated with poorer prognosis

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 Gastroenterology 2012年第7期18卷 712-719页

作者： Wei He Ke Li feng wang yan-Ru Qin Qing-xia Fan De-partment of Oncology the First Affiliated Hospital of ZhengzhouUniversity Zhengzhou 450052 Henan Province China

AIM： To explore the expression pattern of OCT4 in hu- man esophageal squamous cell carcinoma and its sig- nificance in diagnosis and prognosis.

关键词： Esophageal squamous cell carcinoma Im-munohistochemistry OCT4 Real-time polymerasechain reaction Western blotting

Simulation and prediction in laser bending of silicon sheet

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 188-193页

作者： wang Xu-yue XU Wei-xing XU Wen-ji HU Ya-feng LIANG yan-de wang Lian-ji Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of Technology Dalian 116024 China

The laser bending of single-crystal silicon sheet （0.2 mm in thickness） was investigated with JK701 Nd：YAG laser. The models were developed to describe the beam characteristics of pulsed laser. In order to simulate the process of laser bending, the FEM software ANSYS was used to predict the heat temperature and stress-strain fields. The periodic transformation of temperature field and stress-strain distribution was analyzed during pulsed laser scanning silicon sheet. The results indicate that the mechanism of pulsed laser bending silicon is a hybrid mechanism in silicon bending, rather than a simple mechanism of TGM or BM. This work also gets silicon sheet bent after scanning 6 times with pulsed laser, and its bending angle is up to 6.5°. The simulation and prediction results reach well agreement with the verifying experiments.

关键词： laser bending silicon sheet pulsed laser simulation

High-efficiency crystalline white organic lightemitting diodes

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第4期13卷 747-759页

作者： Yijun Liu feng Zhu Yue wang Donghang yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-WOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-WOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(CHM)with embedded nanoaggregates(NA)structure for developing high-performance C-WOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The CHM-TADFNA-D WOLED exhibit a remarkable EQE of 12.8%,which is the highest performance WOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance WOLEDs based on amorphous material route,the C-WOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation WOLEDs.

关键词： diodes dopant crystalline

Magnetic resonance diffusion tensor imaging with fluorescein sodium dyeing for surgery of gliomas in brain motor functional areas

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 Medical Journal 2013年第13期126卷 2418-2423页

作者： LIU Jia-gang yanG Shuai-feng LIU yan-hui wang Xiang MAO Qing Department of Neurosurgery West China Hospital SichuanUniversity Chengdu 610041 China (Liu JG Yang SF Liu YH Wang

Background Tumor surgery in brain motor functional areas remains challenging. Novel techniques are being developed to gain maximal and safe resection for brain tumor surgery. Herein, we assessed the magnetic resonance diffusion tensor imaging （MR-DTI） and fluorescein sodium dyeing （FLS） guiding technique for surgery of glioma located in brain motor functional areas. Methods Totally 83 patients were enrolled according to our inclusion and exclusion criteria （56 patients in experimental group, 27 patients in control group）. In the experimental group, the surgical approach was designed by DTI imaging, which showed the relationship between the tumor and motor tract. The range of resection in the operation was determined using the FLS-stained area, which recognized the tumor and its infiltrated tissue. The traditional routine method was used in the control group. Postoperatively, all patients underwent enhanced brain MRI within 72 hours to ascertain the extent of resection. Patients were followed in our outpatient clinic over 6-24 months. Neurological deficits and Karnofsky scoring （KPS） were evaluated. Results There were no significant differences in balance test indexes of preoperative data （sex, age, lesion location and volume, and neurological deficits before operation） and diagnosis of histopathology between the two groups. There was a trend in the experimental group for greater rates of gross total resection （80.4% vs. 40.7%）, and the paralysis rate caused by surgery was lower in experimental （25.0%） vs. control （66.7%） groups （P 〈0.05）. The 6-month KPS in the low-grade and high-grade gliomas was 91＋11 and 73＋26, respectively, in the experimental group vs. 82＋9 and 43＋27, respectively, in the control group （P 〈0.05 for both）. Conclusions MR-DTI and FLS dye guiding for surgery of glioma located in brain motor functional areas can increase the gross total resection rate, decrease the paralysis rate caused by surgery, and improve patient quality of life compared with

关键词： glioma magnetic resonance diffusion tensor imaging fluorescein sodium dyeing brain motor functional area

Subarachnoid disseminative hemangiopericytoma of the spinal cord

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2010年第11期123卷 1485-1488页

作者： LIN Guo-zhong wang Zhen-yu LI Zhen-dong ZHONG yan-feng wang Lei-ming Department of Neurosurgery Peking University Third HospitalPeking University Beijing 100191 China

Hemangiopericytomas （HPCs） originating from central nervous system were increasingly reportedrecently. Intravertebral HPCs are preclomlnanuy eplaural. Primary intradural HPCs of spinal cord are rare. Little subarach... 详细信息

关键词： hemangiopericytoma cervical spinal cord subarachnoid disseminateion