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Improvement of silicon etching resolution using the confined etchant layer technique

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Chinese Science Bulletin 1997年第15期42卷 1318-1319页

作者： Zu, YB Xie, L Tian, ZW Xie, ZX mu, jq Mao, BW State Key Laboratory for Physical Chemistry of the Solid Surface Department of Chemistry Institute of Physical Chemistry Xiamen University Xiamen China

WHEN scanning electrochemical microscopy (SECM) with feedback mode is used to etchcertain surface, the etchant molecules generated at a microelectrode diffuse to the surface andreact therein with the surface species, resulting in local etching pattern. It is noted that theetching resolution of SECM is dominantly determined by the size of the ***, many experimental results have shown the significant influence of the lateral diffu-sion of etchant on the etching resolution. Therefore, a thin diffusion layer of the

关键词： As SECM Improvement of silicon etching resolution using the confined etchant layer technique CELT

Photochemical reaction of azobenzene in solvent-swollen Nafion membranes

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Chinese Journal of Chemistry 1996年第6期14卷 541-548页

作者： Tung, CH Guan, jq CHINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The photochemical reactions of azobenzene (AB) incorporated into different solvent-swollen Nafion membranes were investigated. The location of azobenzene in water-swollen Nafion membranes was different from that in methanol-swollen Nafion membranes, which was responsible for the different photochemical reactions of AB. In methanol-swollen Nafion membranes only transcis isomerization took place, while in water-swollen Nafion membranes photochemical cyclization of AB occurred after rapid transcis isomerization. The relation between the relative quantum yields and the light intensity showed that the cyclization was a two-photo process. The numbers of AB molecules per cluster (n(AB)/cluster) in Nafion membranes with different AB concentrations and different water contents were calculated. Under the experimental condition two competitive photocyclization mechanisms were suggested by n(AB)/cluster in Nafion membranes, relative quantum yields of the cyclization, and the change of the ratio of benzidine to benzo[c]cinnoline.

关键词： Nafion photochemical reaction azobenzene

Photophysical Behaviors of Azobenzene in Solvent-Swollen Nafion Membranes

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Chinese Chemical Letters 1996年第10期7卷 944-947页

作者： Guan, jq Tung, CH ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

The fluorescence from azobenzene (AB) molecule incorporated into water-swollen Nafion in acid form was observed at room temperature for the first time. The incorporation process was investigated by UV absorption. The plot of the concentration of AB in Nafion vs. the soaking time shows that the adsorption process is diffusion-controlled, and the apparent diffusion coefficient (D) was determined to be 7.6x10(-10) cm(2)s(-1). These results are attributed to the fact that AB molecules are located in the fluorocarbon/water interface of the Nafion membranes and are protonated. In methanol-swollen Nafion membranes, AB fails to fluoresce because it is located at the methanol pool enclosed by the cluster networks.

关键词： Photophysical Behaviors of Azobenzene in Solvent-Swollen Nafion Membranes

Progress in the study on structure and function of the antenna of algae

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Chinese Science Bulletin 1997年第1期42卷 1-7页

作者： Jiang, LJ Zhao, jq Institute of Photographic Chemistry Chinese Academy of Sciences Beijing China

IN the evolution series, algae possess a position between green plants and photosynthetic bacteria. The photosynthetic apparatus of algae and plants are very similar because both of them contain the two phótosynthetic reaction centers of PSⅡ and PSⅠ and have the same photosynthetic function. Therefore, study of the photosynthesis of algae has a common significance. On the other hand, the light-harvesting antennae of plants are chlorophyll a/b-protein complex in thylakoids while those of algae are the phycobilisomes. A phycobilisome is a large super-

关键词： algae antenna structure and function phycobiliproteins phycobilisomes.

Mechanical Alloying Effect on the Structure of Fe-Al-(Si) Alloy

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Journal of Materials Science & Technology 1997年第3期13卷 219-222页

作者： Zhang, jq Wu, BY Hu, Z Wang, GQ SOUTHEAST UNIV DEPT MECH ENGNNANJING 210096PEOPLES R CHINA NANJING UNIV DEPT CHEMNANJING 210008PEOPLES R CHINA NANJING UNIV DEPT PHYSNANJING 210008PEOPLES R CHINA

The mechanical alloying effects on the structures of Fe71.3Al28.4(CeO2)(0.3) and Fe73.3Al9.8-Si-16.6(CeO2)(0.3) samples have been investigated mainly by Mossbauer spectroscopy and X-ray diffraction. it is found that with the increase of milling time, a substituting disordered alpha-Fe solution is formed gradually and almost completed after milled for 72 h. Further increasing milling time causes the atomic rearrangement within the powders. Correspondingly, the average lattice parameter and average crystalline size change until 72 h and remain constant after 72 h. The addition of Si leads to the higher disordered degree reflected in the smaller average hyperfine field and larger mean square deviation.

关键词： Iron alloys

Discovery of Ordovician vertebrate fossil from Inner Mongolia,China

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Chinese Science Bulletin 1997年第18期42卷 1560-1563页

作者： Wang, jq Zhu, M Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China

THE material under study was found from the Zhuozishan Formation (lower Middle

关键词： Inner Mongolia Ordovician vertebrates histology.

Characteristics of major minerals in volcanic ash in ice core from Collins ice cap, King George Island, Antarctic

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Chinese Science Bulletin 1997年第10期42卷 845-850页

作者： Zhang, WH Liu, jq Wang, CJ Lithosphere Tectonic Evolution Laboratory Institute of Geology Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

COLLINS ice cap is located in King George Island south of Shetland Islands,*** icecap is exposed over an area of about 1 300 km^2,amounting to 90% of the *** na-tional scientific expeditions to the Antarctic studied and investigated Collins ice cap systemati-cally from May to October 1992 when they drilled six ice cores in Low ice *** ex-trusion in ice core from Collins ice cap suggested by Dia et *** favourable for

关键词： mineral volcanic ash ice core Collins ice cap Antarctic.

Synthesis and characterization of model conjugate of phycobilisomes

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Chinese Science Bulletin 1997年第17期42卷 1440-1444页

作者： Zhao, jq Zhao, jq Yang, ZX Zhang, JP Jiang, LJ ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

PHYCOBILISOMES are light-harvesting protein-pigment complexes located on the cytoplasmic

关键词： model of phycobilisomes R-phycoerythrin C-phycocyanin allophycocyanin energy transfer.

Recurrence or metastasis of HCC:predictors,early detection and experimental antiangiogenic therapy

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World Journal of Gastroenterology 2000年第1期6卷 61-65页

作者： Jiang YF Yang ZH Hu jq Cancer Institute Chinese Academy of Medical Sciences & Peking Union Medical CollegeBeijing 100021China

AIM To investigate the predictors forrecurrence or metastasis of HCC,and toevaluate the effect of antiangiogenic therapy onthe growth of transplantable human HCC in *** RT-PCR was used to measure theexpression of matrix metalloproteinase-9(MMP-9)and vascular endothelial growth factor(VEGF)in 56 pairs of nontumorous liver andtumor *** blood samples from humanHCC were examined by nested RT-PCR to find outAFP *** human endostatin andpolyclonal antibody against VEGF wereadministered to treat human HCC transplanted innude *** Thirty of 56 HCC samples showedstronger expression of MMP-9 in tumoroustissues than in nontumorous *** ofthe 26 patients with relative expression level ofMMP-9 more than 0.34 developed tumorrecurrence or metastasis,whereas only 7 of 30patients with relative expression level less than0.34 developed tumor recurrence(P<0.05).There was no significant difference in therelative expression level of VEGF betweenpatients with postoperative recurrence ormetastasis and those without *** was detectable in 53.3% of patients *** sensitivity and specificity of AFPmRNA as a marker to detect hematogenousdissemination of HCC cells was 81.8% and84.4%,*** human endostatin and polyclonal antibody against VEGFinhibited the growth of transplantable HCC innude mice by 52.2% and 45.7%,*** MMP-9 expression in HCCcorrelates with the postoperative recurrence ormetastasis of *** with high level ofMMP-9 expression in HCC are susceptible *** mRNA could serve as anindicator of hematogenous spreading of HCCcells in circulation and a predictor of recurrenceor metastasis of *** may bean adjuvant therapy for HCC.

关键词： Subject headings carcinoma Hepatocellular neoplasm metastasis angiogenesis liver neoplasms