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Experimental evaluation of the effect of an internal heat exchanger on a transcritical CO_2 ejector system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第2期12卷 146-153页

作者： Xiao-xiao XU Guang-ming CHEN li-ming TANG Zhi-jiang ZHU Shuang liU Institute of Refrigeration and Cryogenics State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

This study presents experimental results focused on a performance comparison of a transcritical CO2 ejector system without an internal heat exchanger(IHX) (EJE-S) to a transcritical CO2 ejector system with an IHX(EJE-IHX-S) . The comparison includes the effects of changes in operating conditions such as cooling water flow rate and inlet temperature. Experiments are conducted to assess the influence of the IHX on the heating coefficient of performance(COPr) ,heating capacity,entrainment ratio,pressure lift,and other parameters. The primary flow rate of the EJE-IHX-S is higher than that of the EJE-S. The pressure lift and actual ejector work recovery are reduced when the IHX is added to the transcritical CO2 ejector system. Using a more practical performance calculation,the compression ratio in the EJE-S is reduced by 10.0%-12.1%,while that of EJE-IHX-S is reduced only by 5.6%-6.7% compared to that of a conventional transcritical CO2 system. Experimental results are used to validate the findings that the IHX weakens the contribution of the ejector to the system performance.

关键词： CO2 ejector system Transcritical cycle Heating coefficient of performance (COPr)

Post-transcriptional gene silencing signal could move rapidly and bidirectionally in grafted Arabidopsis thaliana

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Chinese Science Bulletin 2006年第3期51卷 313-319页

作者： li ming jiang Shiling WANG Youqun liU Guoqin State Key Laboratory of Plant Physiology and Biochemistry College ofBiological Sciences China Agricultural University Beijing 100094China

RNA interference (RNAi), one of the newly found ways for post-transcriptional gene si- lencing, has been widely used to investigate gene functions through transgenic methods for introducing an RNA silencing signal into plants. In the present study, we constructed a dexamethazone (DEX)-inducible RNAi binary vector harboring a specific sequence fragment (168-bp) homologous to KatB and KatC, two kinesin isoform genes of Arabidopsis, which were proved to result in the post-transcriptional gene si- lencing of KatB and KatC in DEX-induced transgenic plants. RT-PCR and Northern blot analysis on trans- genic homozygous Arabidopsis (termed as RNAi-type plants) showed that DEX inducement causes KatB and KatC mRNA degradation. With a simplified method, Arabidopsis grafting was effectively per- formed between RNAi-type and wild-type lines. The target gene mRNA levels were tested based on semi-quantitative RT-PCR. Our results demonstrateed that DEX-induced gene silencing signals could result in a reduction in KatB and KatC mRNA in the wild-type rootstocks or scions, indicating that silencing signals of RNAi could be transmitted bidirectionally across the graft junction whether RNAi-plants were scions or stocks. In contrast to the previously reported results on grafted tobacco, the transmission of post- tran- scriptional gene silencing signals caused by RNAi in grafted Arabidopsis is more effective than that in to- bacco.

关键词：阿布属嫁接 RNA干预基因抑制信号传导烟草

Novel fluorene-carzazole-based conjugated copolymers containing pyrazoline and benzothiazole segments for blue light-emitting materials

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Chinese Chemical Letters 2007年第12期18卷 1496-1500页

作者： Hao Chen Xing Xu He Gang Yan Xian Rong Cai Ying li Qing jiang ming Gui Xie College of Chemistry Sichuan University Chengdu 610064 China

A series of novel fluorene-carbazole-based copolymers with pyrazoline and benzothiazole units were synthesized successfully through Suzuki coupling reactions. The molecular structures and thermal properties of these polymers were characterized by FTrIR, 1H NMR, DSC and TGA. GPC results indicated that the weight-average molecular weight （Mw） and polydispersity of these polymers were in range （12,0（0）-14,000） and （1.8-2.0）, respectively. The two resulting polymers have high photoluminescence quantum efficiency implying that they may be promising candidates for polymer light-emitting diodes （PLEDs）.

关键词： Fluorene-carbazole copolymers Pyrazoline Bezothiazole

TELLURIUM-CATALYZED DEPROTECTI ON OF ARYL CHLOROACTATES BY SODIUM BOROHYDRIDE

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Chinese Chemical Letters 1993年第4期4卷 315-316页

作者： Xian HUANG li ming jiang Department of Chemistry,Hangzhou University,310028

In the presence of catalytic amounts of tellurium,aryl chloro- acetates can be cleaved by sodium borohydride and regenerate parent phen- ols in good yields.

关键词： TELLURIUM-CATALYZED DEPROTECTI ON OF ARYL CHLOROACTATES BY SODIUM BOROHYDRIDE

New Catalyst for the Copolymerization of Styrene with Carbon Monoxide

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Chinese Chemical Letters 1998年第6期9卷 577-578页

作者： Rong Hua ZHENG Yi Feng ZHANG li ming jiang Zhi Quan SHEN(Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027) Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

Neodymium phosphonate [Nd(P-204)(3)] combined by di(n-butyl) magnesium [Mg(n-Bu)(2)] with hexamethylphosphoramide (HMPA) was first found to be an effective catalyst. The results of infrared spectrum and elemental anal... 详细信息

关键词： carbon monoxide styrene neodymium phosphonate catalyst the St-CO copolymer

Study on the composite Nd:YAG crystal by laser micro-Raman spectroscopy

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Optoelectronics Letters 2007年第6期3卷 441-443页

作者： SUN Dun-lu ZHANG Qing-li WAN Song-ming jiang Hai-he YIN Shao-tang Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences HeFei 230031 China

The composite Nd：YAG crystal with undoped YAG end caps was fabricated by thermal bonding technique. Scanning electron microscopy （SEM） result shows that the width of the bonded interface was about 0.5 lain. The laser micro-Raman was used to study the bonded interface of the composite crystal. The results of Raman spectra and the bonded interface image indicate that the undoped YAG and Nd：YAG crystals have been well bonded together. Furthermore, it can be drawn that the structure and the composition of the bonded interface are the same as the undoped YAG crystal, and that the Nd^3＋ ions do not enter the bonded interface and the YAG side. This property is advantageous to decrease the thermal effect of the boned interface and to improve the laser stability.

关键词：晶体生长 Nd:YAG 物理性质光谱激光

Effects of antisense oligonucleotides of PKC-α on proliferation and apoptosis of HepG₂ in vitro

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Hepatobiliary & Pancreatic Diseases International 2005年第1期4卷 75-79页

作者： Bao-Hua Zhu Zhen-Xiang Yao Shao-Jun Luo li-ming jiang jiang-Wei Xiao Sheng-Chun liu Jin-Biao liu Jian-ming Sun Zhi-Yuan Pei Department of Hepatobiliary Surgery First Affiliated Hospital Chongqing University of Medical Sciences Chongqing 400016 China. baohuazhu@***

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. The long-term survival rate of patients with HCC after prevention and management remains unsatisfactory. In order to provide a novel strategy to cure HCC, we investigated the effects of antisense oligonucleotides of PKC-alpha on proliferation and apoptosis of human hepatoma cell line HepG2 in vitro.METHODS: The human hepatocellular carcinoma cell line HepG2 was cultured and subcultured in RPMI1640 medium in vitro. PKC-alpha antisense oligonucleotides(asODN) of different concentrations with a random sequence as a control were transfected into HepG2 cells by lipofectin(LP). The cell growth index (GI) and the clone formation rate of HepG2 were detected by MTT colorimetric assay and soft agar assay, respectively. The apoptosis rate of HepG2 treated with PKC-alpha asODN was assayed by flow cytometry(FCM). The results were analyzed by SPSS 10.0 software.RESULTS: The GI of HepG2 transfected by PKC-alpha asODN with concentrations ranging from 0.10 micromol to 1.00 micromol were lower significantly than those of control groups (Pliferation of HepG2 and induce its apoptosis by blocking the cell signal transduction related to PKC-alpha in vitro, and may be potentially used in the prevention and management of recurrent and metastatic HCC.

关键词： hepatocellular carcinoma HepG2 PKC-α asODN

Treatment of type C3 distal radius fracture resulted from high-energy injuries by volar plate in combination with external fixator

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Chinese Medical Journal 2009年第13期122卷 1517-1520页

作者： ZHANG Qiu-lin ZHU Xiao-dong li Guo-dong TANG Hao li ming WU Da-jiang Department of Orthopedics Changhal Hospital Second Military Medical University Shanghai 200433 China

Background With a type C3 distal radius fracture it is extremely difficult to maintain the reduction and to restore congruity of the articular surface because the support for the volar and dorsal bone cortex has been lost. An external fixator crossing wrist in combination with Kirschner wire （K-wire） fixation was popularly used by most studies in recent years. But loss of reduction often occurred especially in the volar sides. Methods A total of 30 cases of type C3 distal radius fracture were treated by a volar buttress plate combined with a transarticular external fixator and other techniques such as K-wire fixation and bone grafting if necessary. The postoperative volar tilt angles, ulnar inclinations, radial heights, range of motion, grip strength and complications were recorded to assess the therapeutic effects. Results Of the 30 patients, 27 patients were followed up for 12-29 （mean 18） months and all fractures healed in 8-13 weeks after surgery （mean 10 weeks）. The wrist function was excellent in 8 cases, good in 16 cases and fair in 3 cases according to the Sarmiento scoring system （modified by Stewart）. Conclusions For type C3 comminuted fracture with severe volar and dorsal instability, fixation by volar buttress plate combined with transarticular external fixator should be adopted. Dorsal instability could be further stabilized by other techniques such as Kirschner wire fixation, and bone grafting.

关键词： distal radius fracture internal fixation external fixator

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He li li Sai Wang Shao-jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes