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Improved response surface method for anti-slide reliability analysis of gravity dam based on weighted regression

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第6期11卷 432-439页

作者： Jian-yun CHEN Qiang xy Jing LI Shu-li FAN Qiang xu State Key Laboratory of Coastal and Offshore Engineering Daliatz University of Technology Dalian 116023 China School of Civil and Hydraulic Engineering Dalian University of Technology Dalian 116023 China

The aim of this study was to design and construct an improved response surface method(RSM) based on weighted regression for the anti-slide reliability analysis of concrete gravity *** limitation and lacuna of the traditional RSM were briefly ***,based on small experimental points,research was devoted to an improved RSM with singular value decomposition ***,the method was used on the basis of weighted regression and deviation coefficient correction to reduce iteration times and experimental points and improve the calculation method of checking ***,a test example was given to verify this *** with other conventional algorithms,this method has some strong advantages:this algorithm not only saves the arithmetic operations but also greatly enhances the calculation efficiency and the storage efficiency.

关键词： Response surface method(RSM) Reliability Gravity dam Singular value decomposition Weighted regression Deviation coefficient

Two advances on the photoelectric parallel measuring of spectrum

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Chinese Science Bulletin 1997年第23期42卷 1965-1970页

作者： Lin, LZ Pu, xy Zhang, J Wen, XM Liu, QJ Yunnan Univ Dept Phys Kunming 650091 Peoples R China

THE tendency of the technique of spectral measurement is now towards sensitivity, precision,quickness, time and spatial resolving spectrum. For the spectrophotometers, which acquirespectral data with the serious method, the measurement of spectral intensity for differentwavelengths is not simultaneous. It is difficult to quickly get a spectrum, because time must bespent on tuning the dispersive device, and it is also impossible to process time and spatial Te-solving spectrum. The problems mentioned above are the fatal disadvantages for further devel-oping the spectrophotometer equipped with monochromator. The best way to solve these prob-

关键词： photoelectric parallel measuring of spectrum system’ s resolving power simultaneous spectral width multilayer gratings polychromator.

Geochemistry and petrogenesis of Jurassic high Sr/low Y granitoids in eastern China: Constrains on crustal thickness

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Chinese Science Bulletin 2002年第11期47卷 962-968页

作者： Ge, xy Li, XH Chen, ZG Li, WP Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China

The Jurassic high Sr/low Y granitoids in eastern China are characterized by high Sr/Y (27-166) and La/Yb (14-66) ratios, low abundance in Y (6-21μg/g) and Yb (0.5-2.0μg/g), comparable with those of adakites defined by Defant et al. Thus, they were recently considered as adakitic rocks by some researchers. Compared with the typical adakites in circum-Pacific margins, however, these high Sr/low Y granitoids have higher K2O (-3.5%) but lower A12O3 (-16.0%) as well as lower Mg#(-38) and δSrN (-1.23) values. Furthermore, they show relatively flat HREE patterns with Y/Yb values of -10 close to the chondritic value. These geochemical characteristics indicate a residue mineral assemblage of hornblende, garnet and plagioclase for these high Sr/low Y granitoids melt. Thus, they were generated by partial melting at 9-13 kbar (30-45 km in depth), similar to the Archaean high-Al TTG rather than the modern adakites. Generation of these high Sr/low Y granitoids cannot be considered as evidence for a thickened

关键词： granitoids adakite TTG Jurassic eastern China.

Theoretical investigation on mechanism of dissociation of furan

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Chinese Science Bulletin 1997年第11期42卷 910-914页

作者： Feng, WL Wang, YH Zhang, SW Xi, HW Pang, xy Department of Chemistry Beijing Normal University Beijing China Department of Resource and Engineering Beijing University of Science and Technology Beijing Beijing China Department of Applied Chemistry Taiyuan Industrial University Taiyuan China

RECENTLY much attention has been paid to the mechanism of the dissociation of *** reason is not only that some neutral molecules by ultraviolet（UV）light mayproduce C4H4O+,but also that the investigation of this mech... 详细信息

关键词： furan cation barrier surface of dissociation process transition state intermediate.

Sulfur-driven methylmercury production in paddies continues following soil oxidation

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Journal of Environmental Sciences 2022年第9期34卷 166-174页

作者： Wenli tang Chao tang Pei Lei School of the Environment State Key Laboratory of Pollution Control and Resource ReuseNanjing UniversityNanjing 210023China School of Environment Nanjing Normal UniversityNanjing 210023China

Methylmercury(MeHg) production in paddy soils and its accumulation in rice raise global concerns since rice consumption has been identified as an important pathway of human exposure to MeHg. Sulfur(S) amendment via fertilization has been reported to facilitate Hg methylation in paddy soils under anaerobic conditions, while the dynamic of S-amendment induced MeHg production in soils with increasing redox potential remains unclear. This critical gap hinders a comprehensive understanding of Hg biogeochemistry in rice paddy system which is characterized by the fluctuation of redox potential. Here, we conducted soil incubation experiments to explore MeHg production in slow-oxidizing paddy soils amended with different species of S and doses of sulfate. Results show that the elevated redox potential(1) increased MeHg concentrations by 10.9%-35.2%, which were mainly attributed to the re-oxidation of other S species to sulfate and thus the elevated abundance of sulfatereducing bacteria, and(2) increased MeHg phytoavailability by up to 75% due to the reductions in acid volatile sulfide(AVS) that strongly binds MeHg in soils. Results obtained from this study call for attention to the increased MeHg production and phytoavailability in paddy soils under elevated redox potentials due to water management, which might aggravate the MeHg production induced by S fertilization and thus enhance MeHg accumulation in rice.

关键词： Mercury Sulfur Availability Mercury methylation Rice

Boundary-effect and scale-heating rate equivalence effect of cracking behavior in the rock models subjected to heating from the central borehole

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Science China(Technological Sciences) 2020年第5期63卷 809-818页

作者： HUANG Xin tang ShiBin tang ChunAn State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Thermal cracking is broadly observed in rock engineering.A finite element numerical model which considers the heterogeneity of rock materials and the damage evolution process was used to simulate the thermal cracking behavior of square rock samples heated from the central *** thermal and mechanical behaviors of two cases,i.e.,the case with large size but low heating rate and the case with small size but high heating rate were compared to study the crack initiation location in the models with different model sizes and heating *** simulated stress and temperature fields,as well as the failure pattern,were in good agreement with the experimental *** temperature and thermal stress distribution during the heating process in both cases indicated that high tensile stress was concentrated around the thermal gradient front,which resulted in the cracks initiating at the location with a certain distance away from the *** results show that under the same heating rate,crack initiation location moves outwards with the increment of the model size then remains approximately at one location,which reflects the ***,the results indicate that the relative crack initiation locations in two cases are nearly the same if the ratio between the heating rate in two cases(Tx/Ty)nearly equal to the square of the inverse ratio of corresponding model side lengths((ay/ax)2).This concept is named the scale-heating rate equivalence effect in this *** is beneficial for studying thermal cracking of rock both numerically and experimentally since the model size can be significantly decreased.

关键词： thermal cracking nuclear waste disposal numerical simulation boundary-effect scale-heating rate equivalence effect

THE STACKING INTERACTION OF TERNARY COMPLEXES OF Zn (ATP)^(2-) AND PYRIDINE-LIKELIGANDS

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Chinese Chemical Letters 1995年第9期6卷 801-804页

作者： Le, xy Wu, FH Song, FY Ji, LN Zhongshan Univ Dept Chem Guangzhou 610275 Peoples R China Nanjing Univ State Key Lab Coordinat Chem Nanjing 210008 Peoples R China

Abstract: The stability constants of ternary complexes of the type Zn (ATP) L2-.,where L=pyridine, 4-7 icoline, 3, 4- lutidine and 3, 5- lutidine,have been determined by potentiometric pll titration in aqueous solution and compared with the stabililty of the corresponding binary complexes ZuL2+. It has been observed that there is a stacking interact ion between the pyridine ring of the pyridine-like the ligands and the purine moiety of ATP in the ternary Zn (ATP) La- complexes and this stacking interaceion is stronger than that in corresponding Cu (ATP) L2- complexes.

关键词： ATP COMPLEXES Zn AND

Bi-based superconductors fabricated in high magnetic fields

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中国有色金属学会会刊：英文版 2006年第B1期16卷 11-19页

作者： LU xy A. NAGATA K. SUGAWARA K. WATANABE T. NOJIMA Faculty of Engineering and Resource Science Akita University Akita 010-8502 Japan Institute for Materials Research Tohoku University Sendai 980-8577 Japan Center for Low Temperature Science Tohoku University Sendai 980-8577 Japan

The microstructure and superconducting properties of Bi-2223 superconductor fabricated in high magnetic fields were investigated. The results shows that the Bi-2212 grains with their c-axis parallel to the magnetic field were formed after the partial-melting and solidification in 8 T magnetic field, and transformed into the Bi-2223 grains with c-axis alignment during the further sintering process at 840 ℃ without magnetic field. The conversion of Bi-2212 grains to Bi-2223 grains has the heredity in grain alignment. The mixed structures of the Bi-2223 and the Bi-2212 grains with their c-axis parallel to the magnetic field are formed in samples sintered at 850?855 ℃ in 10 T magnetic field. When sintered in 10 T below 845 ℃, a high proportion of Bi-2223 phase is obtained, however no preferred orientation is observed. The Bi-2223 grains with their c-axis parallel to the axial direction of the vertical tube furnace are formed not only on the surface, but also in the center of the sample sintered at 850 ℃ for 120 h in a 15 ℃/cm temperature gradient without magnetic field. Moreover, the samples sintered in the temperature gradient and in a 10 T magnetic field have a stronger c-axis alignment of Bi-2223 phase.

关键词：铋基超导体制造铋-2223 磁场显微结构

Portal vein embolization by fine needle ethanol injection :experimental and clinicalstudies

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World Journal of Gastroenterology 1999年第6期5卷 506-510页

作者： Lu MD Chen JW Xie xy Liang LJ Huang JF Sun Yat Sen Univ Med Sci Affiliated Hosp 1 Dept Hepatobiliary Surg Guangzhou 510080 Guangdong Prov Peoples R China

AIM To improve the technique of intraportal embolization (PVE) therapy, a new embolic method, was devised and the safety, effectiveness and feasibility were evaluated. METHODS PVE with intraportal ethanol injection via a fine needle was performed in 28 normal dogs, 22 SD rats, and 24 cirrhotic SD rats. After PVE, portography, histological and functional alteration of the liver were evaluated in dogs and rats, and the changes in portal hemodynamics as well as hepatic anatomy were observed in rats. In the clinical study, PVE by ethanol injection was performed in 61 patients with hepatocellular carcinoma under the guidance of portoechography with intraportal injection of CO 2. The effect of PVE was evaluated by ultrasonography and laparotomy. RESULTS The effectiveness and toxicity were dependent on the dose of ethanol. In the dogs, 0 25*!mg/*!kg of ethanol caused incomplete embolization with least liver damage, while 1 0*!mg/*!kg induced complete embolization with a high mortality of 57 1% (4/*!7) due to respiratory arrest. The dose of 0 5*!mg/*!kg resulted in complete embolization with slight toxicity to the liver. In the rats, the survival rate was 100% in normal group but 40 9% in cirrhotic models after ethanol injection by dose of 0 05*!mg/*!100*!g . PVE for cirrhotic rats with 0 03*!mg/*!100*!g of ethanol induced satisfactory embolization with significant hypertrophy in nonembolized lobes, and only slight damage to the hepatic parenchyma, and transient alteration in liver function, portal pressure and portal flow. In the clinical study, 12 cases with reverse portal flow were excluded judged by portoechography. Satisfactory embolization was gained in 90 2% (55/*!61) of the remaining patients determined by ultrasonography and surgery. All cases ran an uneventful postembolization course with no aberrant embolization. CONCLUSION PVE with intraportal ethanol injection of appropriate dosage via a fine needle is safe and effective and has several advantages comparing wit

关键词： liver neoplasms/therapy portal vein embolization enthanol injection carcinoma, hepatocellular/therapy