Manganese oxide La_0.7Sr_0.3MnO₃ produced on (001) LaAlO₃ substrate by means of sol-gel spin-coating method was used as the base electrode of LaSrMnO/Al₂O₃/Fe tunnel junctions. The I-V characteristic in the high bias region of this system was shown to be similar to that of the conventional tunnel junctions. Anomalous temperature dependence of tunneling resistance was observed to be a positive temperature coefficient of resistance. This phenomenon was attributed to the high voltage applied and was simply elucidated from the density states vs. energy diagram.

A new method for the generation of orthogonal body-fitted grids is presented in this paper. The positions of boundary points in the physical domain are adjusted to obtain orthogonal curvilinear grids without changing the value of ξ and η during the numerical process. The densities of ξ and η are given in advance. Good results were achieved in the application of this method on the cooling system of an internal combustion engine and a trail duct.

Numerical investigations were carried out to determine the coupled heat transfer of water-saturated porous media with a two-phase closed thermosyphon for soil freezing, and to examine the characteristics of the freezing heat transfer in the water-saturated porous media. The whole control volume includes the thermosyphon and the porous media. The two-dimensional governing equations for the water-saturated porous media are used.\n The conjugation of heat transfer between the thermosyphon and porous media is reflected through thermal balance between the thermosyphon and the porous media.\n The finite-difference method was used to solve the two-dimensional governing equation for the water-saturated porous media and the heat transfer characteristics of the thermosyphon, obtain the flow fields and the temperature distributions in the soil. This paper deals mainly with the effect of some factors (such as soil properties, climate and thermosyphon dimensions) on the heat transfer rate of the thermosyphon and the growth of the freezing front. The predictions of the present study agree well with the measured data.

This paper presents a synthetic design procedure for a robust LQ regulator for refining process, including modeling and robust optimal system designing. The paper discusses three major topics: mathematical modeling of the process with large uncertainty, determination of a synthetic performance index for optimizing the process, and design of the robust optimal system with robust guaranteed stability. This research result is a part of preliminary results of the real refining process optimal control system implemented in the Minfeng Paper Mill, Zhejiang Province. Simulation test results showed that the proposed modeling and control algorithm are efficient and practicable.

Voluminous statistical data on the breakage and leakage of pipelines occurring frequently in water supply and drainage engineering, were collected and analyzed to find the causes and solutions for the breakage and leakage. Then the original parameter method of foundation beam on elastic semi-infinite plane subgrade was applied to verify the statistical results. Numerical computational results showed that the performance of the original parameter method of foundation beam was satisfactory.

A new model was developed to describe the diffusion limitation on free radical polyme-rization. In this model the termination rate coefficient (k_t) and propagation rate coefficient (k_p) were expressed as a function of bulk viscosity (η). This model was used to simulate the batch thermal polymerization of styrene (St) and the continuous thermal bulk copolymerization of St (monomer 1) and maleic anhydride (MAH, monomer 2) in a CSTR with on-line monitor of the rheological behavior. The simulated results on polymerization conversion, copolymer composition, molecular weight and its distributions were compared with the experimental data, and the results calculated by two previous gel-effect models i.e. Martin-Hamielec and Tulig-Tirrell models. It was found that the present model produces better prediction than that of the Tulig-Tirrell model and has the same accuracy as that of the Martin-Hamielec model, but is much simpler.

A new catalyst composed of Tin-bridged yttrocene Ph₂Sn(MeCp)₂YCl (MeCp=methylcyclopentadienyl) and Al(i-Bu)₃ was successfully developed for the polymerization of methyl methacrylate(MMA). Detailed study of factors (such as the molar ratio of Al/Cat., catalyst concentration, various solvents, temperature and time) influencing polymerization reaction indicated that the catalytic active species may be still somewhat stable at high temperature and still have a long catalytic lifetime. ¹H NMR spectrum showed about 65% syndiotactic content in the polymethyl methacrylate(PMMA) prepared. From kinetic studies, the polymerization rate equation may be expressed as Rp=Kp[Cat.]^2.4. The overall activation energy of polymerization is 20.9±3.1 kJ/mol.

The whole process of octadecyltrichlorosilane (OTS) self-assembled monolayer formation on glass surface was clearly revealed by using Atomic Force Microscope (AFM). The growth regularity pattern of OTS self-assembled monolayer on glass substrate was obtained by analyses of the AFM images and the average surface mean roughness (R_avg) of the sample surfaces. The adsorption feature of\nOTS molecules on the substrate surface during the initial reaction period was probed through a comparison experiment.

A series of high molecular weight PVC (HMW-PVC) resin was synthesized by suspension process at various temperatures and compounded to prepare plasticized HMW-PVC. Plasticized HMW-PVC is physically crosslinked by microcrystallites and chain entanglements. The molecular weight and degree of crystallinity of PVC resin increase with decrease of polymeri-zation temperature. More dense physical crosslinking networks are formed in plasticized PVC with the decrease of polymerization temperature of PVC resin. Plasticized HMW-PVC exhibits thermal reversible processability, but the gelation temperature and melt viscosity increase with increasing physical crosslinking density. Physical crosslinking also has great effects on the mechanical properties of plasticized HMW-PVC. The compression set and deformation decrease as molecular weight and crystallinity of PVC resin increase, but the softening temperature and tensile strength increase. The crosslinking network of plasticized HMW-PVC is more similar to the dissociable network of gels than to the permanent network of crosslinked rubber and is not stable under stretching at high stress.

In this study, the structure of nanocrystalline CaCO₃ was analyzed using TEM, SEM, FT-IR and XRD measurements. An unusually narrow v₃ band with remarkable blue shift about 40 cm^-1 in the infrared spectrum was observed. XRD analysis revealed a somewhat large crystallite strain in the nano-particle CaCO₃. The strain was possibly related to the weakened lattice vibration. This suggests a preliminary explanation for the abnormal IR assimilation characteristics of nanocrystalline CaCO₃ aforementioned.

The syntheses and characterization of six new spin labeled phenoxyacetates as potential auxins are described.

The structure of a novel lactam(I) isolated from Delphinium caeuleum Jacq.ex Camb was determined by spectral data.

This phytochemical study on Euonymus alatus (Thunb.) Sleb. (Celestrceae) yielded two compounds: a new compound, 2,3-dihydroxypropanyl hentetracosanate and a known compound: neozeaxanthin A. Their structures were elucidated by spectral evidences.

Two common fish species, mosquitofish (Gambusia affinis) and topmouth gudgeon (Pseudorasobora parva ) were exposed to different concentrations of fenitrothion in static system for 96 h. Hepatic glutathione S-transferase activity was evaluated after 48 and 96 h pesticide exposure, and was also examined in fish pretreated with pepironyl butoxide and triphenyl phosphate and then exposed to fenitrothion. Results indicated presence of intense glutathione S-transferase activity in both species, mosquitofish exhibiting the higher activity. In both species the activity decreased as the concentration of fenitrothion increased, topmouth gudgeon being more susceptible than mosquitofish. In mosquitofish pretreated with pepironyl butoxide, glutathione S-transferase activity was increased (11.8%) comparded with the control but in topmouth gudgeon it was decreased (21.6%) at the end of 96 h. Glutathione S-transferase activity was significantly reduce in both species pretreated with triphenyl phosphate at the end of 96 h exposure, topmouth gudgeon being highly susceptible.

A laboratory incubation experiment was conducted to study the effect of copper as cupric sulfate (CuSO₄·5H₂O), and lead as lead acetate (Pb(OAc)₂) on the size of the microbial biomass in red soil. The metals were applied, separately at six different levels: Cu at 50, 100, 200, 300, 400, and 600 μg·g^-1 soil and Pb at 100,200,400,600,800,and 1000 μg·g^-1 soil. In comparison to uncontaminated soil, the microbial biomass carbon (C_mic) and biomass nitrogen (N_mic) decreased sharply in soils contaminated with Cu and Pb. The microbial biomass C:N ratio in the metal contaminated soil was observed to be considerably higher than that in untreated control. Between the two tested metals, Cu displayed greater biocidal effect on microbial biomass carbon and nitrogen than Pb, showing their relative toxicity in the order: Cu>>Pb.

To gain better understanding of telomerase\'s possible role in the carcinogenesis of gestational trophoblastic tumors, the authors conducted RT-PCR amplification-based analysis and carried out telomeric repeat amplification to determine the levels of the human telomerase RNA (hTR) and that of telomerase enzymatic activity itself in 43 normal human placental tissues, 35 gestational trophoblastic tumor tissues and three choriocarcinoma cell lines. hTR was expressed in malignant gestational trophoblastic tumor tissues as well as choriocarcinoma cell lines. The results showed that hTR of early placenta villi and a part of hydatidiform mole were positive. But relatively low levels of the hTR could be found in placental tissues. Telomerase enzymatic activity was strongly positive in 32 of the 35 (91.4%) gestational trophoblastic tumor tissues and all the three choriocarcinoma cell lines. The enzymatic activity of telomerase itself was detectable at relatively low lelves in 14 of the 21 (66.7%) early placental villi, only three of the 22(13.6%) term placenta were weakly positive. These results suggest that telomerase activity may be correlated with the development of trophoblastic tumors, and so, may be a useful diagnostic marker for detecting the existence of malignant trophoblastic cells.

The molecular cloning of the G₁ genome segment of the Z₁₀ strain of Hantaan virus and analysis of the first gene data on the currently widely used Hantavirus vaccine strain in China are presented. The G₁ genome segment of Z₁₀ virus was amplified by the method of RT-PCR, and the products were cloned into the pGEM-T vector after identification and purification. The clone was sequenced by Sanger\'s dideoxy chain termination method. The 1449 bases of the Z₁₀ G₁ genome segment ,and the coding for 483 amino acids were determined. The base compositions for the G₁ segment RNA determined from cDNA sequence information , were 20.6% A, 21.6% G, 18.8% C and 30.0% U. These values are similar to those of the 76/118, Lee and SR virus. As compared to the Z₁₀ G₁ segment, the sequence homology at the nucleotide level is 87%(76/118, type I), 86% (Lee, type I),86% (Hojo, type I), 67%(R22,type II), and 59%(K22, type III).The Z₁₀ virus G₁ protein amino acid sequence identity with other Hantaan viruses (94-95% homology) was higher than that with Seoul type viruses (77-80%). More amino acid sequence heterogeneity between the Z₁₀ and 76/118 was observed in the N terminal, especially the diverging cluster of ten amino acids at position 84 to 93 of the Z₁₀ virus G₁ protein. Conclusion:(1) The Z₁₀ strain is one of the Hantaan viruses. (2) The important region of the Z₁₀ G₁ segment was conservative. (3) Although substantial divergence of nucleotide sequences of the G₁ genome segment was found between the Z₁₀ strain and other type I Hantaviruses, relatively high amino acid sequence homology was shown among them. Thus, good immune protection could be obtained with the inactivated Meriones unguiculatus kidney cell vaccine against other strains of Hantaviruses.

This study was carried out to elucidate the nephroprotective effects from a mixture of 8 L-amino acids and the possible mechanism of protection by this amino acid mixture. Acute renal failure model was induced by an intravenous administration of 10 mg/kg cisplatin to male Sprague-Dawley rats. A mixture of 8 L-amino acids or 0.9% saline was infused at a rate of 2 ml/h for 3 h, starting with a 2 ml bolus injection before cisplatin administration. Amino acids showed no acute effect on renal morphology. The infusion of a mixture of 8 L-amino acids increased GFR by 85% in control rats. The abnormalities of urine sodium and potassium excretion caused by cisplatin were markedly attenuated by the administration of the amino acid mixture. With the infusion of this amino acid mixture, cisplatin-induced abnormal state 4 respiration returned to control levels and the depressed state 3 respiration, respiratory control ratio and carbonyl cyanide p-trifluoromethoxyphenyl hydrazone-uncoupled respiration were ameliorated remarkably. A mixture of 8 L-amino acids showed marked nephroprotection against cisplatin-induced acute renal failure in rats and might function through augmentation of the cisplatin-injured renal mitochondrial electron transport-oxidative phosphorylation sequence, probably via stabilizing the membrane (including inner mitochondrial membrane) protein tertiary structure. In addition, this amino acid mixture remarkably increased GFR and decreased urine sodium excretion in rats.

In order to find a safe, simple, effective and selective pulmonary vasodilator, we tested the effectiveness and safety of inhalation of nebulized nitroglycerin (Neb-NTG) by children with ventricular septal defect and pulmonary hypertension (VSD-PH). Twenty μg/kg Neb-NTG was inhaled by seven children with VSD-PH using face mask during cardiac catheterization. The pulmonary artery pressure (PAP), systemic arterial pressure (SAP) and methemoglobin (MetHb) concentration were measured before and after inhalation of Neb-NTG. After inhalation of Neb-NTG, the PAP and pulmonary-to-systemic pressure ratio (Pp/Ps) decreased significantly; There was no significant decrease in SAP. The systolic and diastolic PAP decreased respectively 13±4% and 9±7% in 5 min, 21±3% and 13±17% in 10 min, 24±3% and 16±19% in 15 min. The Pp/Ps decreased 12±4% in 5 min, 21±9% in 10 min and 24±6% in 15 min. There was no significant increase in the MetHb level after inhalation of 20 μg/kg of Neb-NTG. The MetHb level was below 1.5%. Neb-NTG is a safe, simple, effective and selective pulmonary vasodilator.

The clinical diagnosis of sepsis is difficult, particularly in neonates. To devise a rapid and reliable method for identifying bacteria in blood and cerebrospinal fluid (CSF), we developed a pair of primers according to the gene encoding 16 s rRNA, found in all bacteria. DNA fragments from different bacterial species and from clinical samples were detected with polymerase chain reaction (PCR), and with reverse hybridization using a universal bacterial probe, a gram-positive probe and a gram-negative probe. Our results showed that a 371 bp DNA fragment was amplified from 20 different bacterial species. No signal was observed when human DNA and viruses were used as templates. The sensitivity could be improved to 10^-12 g. All 26 culture-positive clinical samples (22 blood samples and 4 CSF samples), were positive with PCR. The gram-negative and gram-positive probe hybridized to clinical samples and to known bacterial controls, as predicted by Gram

To study the relationship between ulcer recurrence and Helicobacter Pylori. 147 patients with peptic ulcer were divided into H. Pylori infected group and H.pylori uninfected group by rapid urease test, serum antibody examination and histopathology of gastric biopsy specimens. We assigned all patients to receive dual oral therapy with omeprazole 40 mg/day for 4 weeks and amoxicillin 2000 mg/day for 2 weeks. To all patients, repeated gastroscope was performed at 8 weeks and one-year after beginning therapy to record whether the ulcer was cured. Endoscopic biopsy was also performed to dertermine H.pylori status. One year later, H.pylori positive patients had a higher ulcer recurrent rate than H.pylori negative patients(23.33% vs 2.70%; P=0.001). Ulcer recurrence was closely related to H.pylori infection. H.pylori was the risk factor for ulcer relapse.

Indigenous technological innovation capability-building has emerged in recent years as a new development agenda and the critical problem in China. This paper, based on 5-year empirical research on Chinese firms and theoretical analysis, presents and details the contents of a \"3-I innovation strategy,\" and finally shows the industrial difference of such strategy.

The resolution of the problem of Urban Residence is important for realization of Sustainable Human Settlements. Along with the acceleration of urbanization in China, all aspects concerning the problem of urban residence are undergoing gradual changes. This thesis expounds on \"The Order Diagram by Expression of Social Requirement to Habitation\" and an \"External Relationship System of Residence\" and also puts forward a series of problems, requiring special consideration in achieving sustainable development of Chinese urban residence.

The urban physical environment results not only from functional requirements of urban life, but also from the very cultural background and social relationships. After examining the relationships between the architecture and the cultural contexts in Paris, the author presents and argues a belief that the architectural characteristics in Paris can be better explained by understanding the Parisian ways of urban life.