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Nucleation and growth mechanism of cefodizime sodium at different solvent compositions

Xinwei ZHANG, Shudong ZHANG, Xiaodan SUN, Zequn YIN, Quanjie LIU, Xiwen ZHANG, Qiuxiang YIN

《化学科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 490-495 doi: 10.1007/s11705-013-1350-5

摘要: The induction time of cefodizime sodium was measured in ethanol-water at different solvent compositions by the laser technology measurement. The results indicate that the solvent composition played an important role in the supersaturation and the nucleation process of cefodizime sodium solution. According to the modified classical nucleation theory, the nucleation and growth mechanism were identified. The correlation results show that heterogeneous nucleation dominated the nucleation process at lower supersaturation, where homogeneous nucleation is the most important mechanism at higher supersaturation. Based on the correlated results, the 2D mediated growth mechanism had the highest correlation coefficients ( ), so this mechanism was selected as the proper growth mechanism for cefodizime sodium.

关键词: cefodizime sodium     induction time     primary nucleation     growth mechanism    

Bioengineering protection mechanism of city rock slope and its laboratory test

Desong JIANG, Minghua ZHAO, Chong JIANG,

《结构与土木工程前沿(英文)》 2009年 第3卷 第4期   页码 414-421 doi: 10.1007/s11709-009-0055-9

摘要: Based on the features of rock slope bioengineering protection, the ecology protection mechanism of the urban rock slope was discussed with the mechanics effect of plants and rock slope, and the reinforcement action mechanism of rock slope by plant root system was analyzed as well. Then, the corresponding mechanical model was proposed, from which the formula to calculate the increased shearing strength of the root system-earth compound body was derived. Moreover, the side slope rainfall interception, the runoff lagging, the soil antiseepage, and the soil layer consolidating effect were studied, respectively. Furthermore, the indoor model experiment of urban crag rock slope ecology protection was designed and completed, in which various grasses to plant in slope with different angles, solid earth forms, and the different strengthening earth mechanism were studied. Finally, the present method was applied in an engineering project, from which the antiwashing behavior of three kind of grasses (i.e., the Bahiagrass, the tall fescue, and the Bermudagrass) planted in the slope with an angle of 38°, 48°, and 58°, respectively, and different strengthening structures (i.e., the diamond wire netting, the geocell and the three-dimensional network) were obtained. The application results also show that the effect of geocell structure is the best one followed by the three-dimensional net and the diamond wire net. The antiwashing capability per unit area has a critical slope angle of about 25°. The reinforcing effect of Bermudagrass is better than the Bahiagrass and tall fescue.

关键词: indoor     engineering project     protection mechanism     different     runoff lagging    

Not asthma, but GERD: case report

WANG Zhonggao

《医学前沿(英文)》 2007年 第1卷 第1期   页码 115-119 doi: 10.1007/s11684-007-0022-6

摘要: Asthma is a disorder of the lungs characterized by increased responsiveness of the airways, as manifested by episodes of wheezing and increased resistance to expiratory airflow because of varying degrees of smooth muscle contraction, edema of the mucosa, and mucus in the lumen of the bronchi and bronchioles. The stimuli vary widely and include antigens, infection, air pollutants, respiratory tract irritants, exercise, and emotional factors. This condition is completely different from distress breathing because of laryngotracheal spasm. One of its causes is the gastric content reflux through the pharynx to the larynx because of gastroesophageal reflux disease (GERD), in addition to the typical human avian flu that may cause immediate suffocation by laryngospasm owing to acute larygotrachitis. A patient suffered from GERD without esophageal symptoms, which was diagnosed and treated as bronchial asthma during his five emergency admissions. The admissions were because of episodic attacks of severe air hunger owing to an extreme throat tightening. The patient was being treated for as long as two years. After the correct diagnosis was made and treatment of laporascopic fundaplication was performed, the longstanding bronchial asthma , after all, completely disappeared. The concept of not asthma, but GERD seems undervalued, unappreciated, even misunderstood among patients with intractable asthma. Therefore, such a case is reported in detail, similar cases are mentioned briefly as well, and a mechanism responsible for GERD-originated larryngo- or laryngotracho-spasm is proposed.

关键词: resistance     mechanism responsible     unappreciated     responsiveness     different    

Ecological compensation mechanism for urban green land and its application in Shanghai, China

WANG Yan, DING Xiaowen, QIAN Longxia, WANG Hongrui

《环境科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 320-324 doi: 10.1007/s11783-007-0054-9

摘要: Urban green land compensation plays an important role in county development, ecological environment management and many other fields. The concept, methods and principles of urban green land are introduced in this paper. According to the pay fee method, the value and ecological function of various types of urban green land were analyzed. The cost-benefit analysis method (CBAM) was used to estimate different external diseconomy benefits caused by green land loss. The authors applied CBAM to estimate such benefits in the case of Shanghai, China, and calculated the actual compensation value for green land. Results indicated that in 2002, the compensation value for the green land of Shanghai was RMB 8.58 × 10 Yuan/hm.

关键词: development     Yuan/hm     different external     concept     cost-benefit analysis    

Numerical analysis of rotating stall characteristics in vaneless diffuser with large width-radius ratio

GAO Chuang, GU Chuangang, WANG Tong, DAI Zhengyuan

《能源前沿(英文)》 2008年 第2卷 第4期   页码 457-460 doi: 10.1007/s11708-008-0071-9

摘要: A two-dimensional model, where the influence of wall boundary layers is neglected and inlet jet-wake velocity patterns are prescribed, was applied to simulate one vaneless diffuser with a large width-radius ratio. The impact of diffuser length, impeller blade number, etc. on the rotating stall was analyzed. Computational results show that a different mechanism does exist for diffusers with large width-radius ratios. Comparison with related conclusions and references is supportive of the model.

关键词: Comparison     Computational     two-dimensional     influence     different mechanism    

Abnormal expression of c-Myc in human bronchial epithelial cells malignantly transformed by anti-BPDE

FU Juan, JIANG Yiguo, CHEN Xuemin

《医学前沿(英文)》 2008年 第2卷 第4期   页码 380-385 doi: 10.1007/s11684-008-0073-3

摘要: Anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (anti-BPDE) is a metabolite of benzo[a]pyrene (B[a]P) and acts as a potent mutagen in mammalian systems. However, molecular mechanisms related to anti-BPDE-induced carcinogenesis are poorly understood. Here, we investigated the expression of proto-oncogene c- in human bronchial epithelial cells (16HBE-T) transformed by exposure to anti-BPDE. The levels of mRNA and protein of c-Myc were examined in the 16HBE-T and vehicle-treated control cells (16HBE-N) by using different methods respectively, including reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative real-time PCR (Q-PCR), western blot and immunocytochemical methods. The level of c- mRNA appeared to be significantly increased in 16HBE-T, as compared with those of the 16HBE-N. Likewise, the expression of c-Myc protein was significantly enhanced as compared with those of the control cells. Moreover, the localization of c-Myc protein shows mainly nuclear staining in 16HBE-T. In conclusion, the abnormal expression of c-Myc was present in anti-BPDE malignantly transformed 16HBE cells, which may be involved in the carcinogenesis molecular mechanism of anti-BPDE.

关键词: transcriptase-polymerase     vehicle-treated     understood     molecular mechanism     different    

A review on different theoretical models of electrocaloric effect for refrigeration

《能源前沿(英文)》 2023年 第17卷 第4期   页码 478-503 doi: 10.1007/s11708-023-0884-6

摘要: The performance parameters for characterizing the electrocaloric effect are isothermal entropy change and the adiabatic temperature change, respectively. This paper reviews the electrocaloric effect of ferroelectric materials based on different theoretical models. First, it provides four different calculation scales (the first-principle-based effective Hamiltonian, the Landau-Devonshire thermodynamic theory, phase-field simulation, and finite element analysis) to explain the basic theory of calculating the electrocaloric effect. Then, it comprehensively reviews the recent progress of these methods in regulating the electrocaloric effect and the generation mechanism of the electrocaloric effect. Finally, it summarizes and anticipates the exploration of more novel electrocaloric materials based on the framework constructed by the different computational methods.

关键词: electrocaloric effect     effective Hamiltonian     phase-field modeling     different theoretical models    

Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

ZHOU Hongbo, CHEN Zhuchang

《结构与土木工程前沿(英文)》 2007年 第1卷 第4期   页码 458-463 doi: 10.1007/s11709-007-0062-7

摘要: Based on the comparative analysis of end effect on skin friction of displacement-pile (driven pile), the end effect on skin friction of bored pile is studied. The end effect on skin friction between driven pile and bored pile is different and the end effect on skin friction of bored pile is reduce of skin friction in the soil layer adjacent to the pile end. The degradation degree of skin friction is deduced with the increase of the distance from pile end. The concept of additional mud cake formed by the effect of cushion at the bottom of borehole during pouring concrete is introduced to explain the mechanism of end effect on skin friction of the bored pile. The test results of post-grouting piles indicate that the post-grouting technique is an effective way to improve the end effect on skin friction of bored pile.

关键词: distance     different     concept     additional     bottom    

Characterization and catalytic properties of mesoporous CuO/SBA-16 prepared by different impregnation

DONG Yongli, YUAN Fulong, ZHU Yujun, ZHAO Lina, CAI Zhicheng

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 150-154 doi: 10.1007/s11705-008-0036-x

摘要: CuO/SBA-16 catalysts were prepared by two different routes – the conventional impregnation method and the modified impregnation method with pH adjustment. These catalysts were characterized by X-ray diffraction (XRD), atomic absorption spectrometry (AAS), N physisorption and hydrogen temperature programmed reduction (H-TPR) measurements which reveal that the cubic cage-like () pore structure of the parent SBA-16 molecule sieves was well maintained throughout the synthesis. After introduction of Cu, a different CuO dispersion exists on these catalysts. The CuO/SBA-16 prepared by modified impregnation method has a single highly dispersed CuO which is considered as a highly efficient species for hydroxylation of phenol with HO. CuO/SBA-16 prepared by the conventional impregnation method shows the presence of bulk CuO species which is undesirable for this reaction.

关键词: different     CuO/SBA-16     temperature     physisorption     introduction    

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

《结构与土木工程前沿(英文)》 2021年 第15卷 第6期   页码 1390-1399 doi: 10.1007/s11709-021-0775-z

摘要: High viscosity asphalt (HVA) has been a great success as a drainage pavement material. However, the larger porosity of drainage asphalt mixtures weakens the cohesion and adhesion and leads to premature rutting, water damage, spalling and cracking. The purpose of this study was to investigate the rheological properties of HVA prepared using different high viscosity modifiers through conventional tests, Brookfield viscosity tests, dynamic shear rheometer tests and bending beam rheometer tests. The conventional performance results demonstrated SBS + rubber asphalt (SRA-1/2) exhibited excellent elastic recovery and low-temperature flexibility. The 60°C dynamic viscosity results indicated TPS + rubber asphalt (TRA) had the excellent adhesion. The rotational viscosity results and rheological results indicated that SRA-2 not only exhibited excellent temperature stability and workability, as well as excellent resistance to deformation and rutting resistance, but also exhibited excellent low-temperature cracking resistance and relaxation performance. Based on rheological results, the PG classification of HVA was 16% rubber + asphalt for PG76-22, 20% rubber + asphalt for PG88-22, TRA and SRA-1/2 for PG88-28. From comprehensive evaluation of the viscosity, temperature stability and sensitivity, as well as high/low temperature performance of HVA, SRA-2 was found to be more suited to the requirements of drainage asphalt pavement materials.

关键词: high viscosity asphalt     rheological properties     rubber     modifier     viscosity    

Enhanced performance of oxygen vacancies on CO adsorption and activation over different phases of ZrO

《能源前沿(英文)》 2023年 第17卷 第4期   页码 545-554 doi: 10.1007/s11708-023-0867-7

摘要: The effect of oxygen vacancies on the adsorption and activation of CO2 on the surface of different phases of ZrO2 is investigated by density functional theory (DFT) calculations. The calculations show that the oxygen vacancies contribute greatly to both the adsorption and activation of CO2. The adsorption energy of CO2 on the c-ZrO2, t-ZrO2 and, m-ZrO2 surfaces is enhanced to 5, 4, and 3 folds with the help of oxygen vacancies, respectively. Moreover, the energy barrier of CO2 dissociation on the defective surfaces of c-ZrO2, t-ZrO2, and m-ZrO2 is reduced to 1/2, 1/4, and 1/5 of the perfect surface with the assistance of oxygen vacancies. Furthermore, the activation of CO2 on the ZrO2 surface where oxygen vacancies are present, and changes from an endothermic reaction to an exothermic reaction. This finding demonstrates that the presence of oxygen vacancies promotes the activation of CO2 both kinetically and thermodynamically. These results could provide guidance for the high-efficient utilization of CO2 at an atomic scale.

关键词: CO2 activation     oxygen vacancies     ZrO2     different phases    

Untargeted metabolomic analysis of pregnant women exposure to perfluorooctanoic acid at different degrees

《环境科学与工程前沿(英文)》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1628-x

摘要:

● Metabolome can distinguish pregnant women exposure to PFOA at different degrees.

关键词: Perfluorooctanoic acid     Exposure     Pregnant women     Metabolomic     GSH     Microbiota metabolism    

Effectiveness of tertiary treatment processes in removing different classes of emerging contaminants

《环境科学与工程前沿(英文)》 2022年 第16卷 第11期 doi: 10.1007/s11783-022-1583-y

摘要:

● Different advanced treatment processes were tested for ECs removal from wastewater.

关键词: Micropollutants     Wastewater     PAC     Membranes     UV     Tertiary treatment    

Multiple regression models for energy consumption of office buildings in different climates in China

Siyu ZHOU, Neng ZHU

《能源前沿(英文)》 2013年 第7卷 第1期   页码 103-110 doi: 10.1007/s11708-012-0220-z

摘要: The energy consumption of office buildings in China has been growing significantly in recent years. Obviously, there are significant relationships between building envelope and the energy consumption of office buildings. The 8 key building envelope influencing factors were found in this paper to evaluate their effects on the energy consumption of the air-conditioning system. The typical combinations of the key influencing factors were performed in Trnsy simulation. Then on the basis of the simulated results, the multiple regression models were developed respectively for the four climates of China—hot summer and warm winter, hot summer and cold winter, cold, and severely cold. According to the analysis of regression coefficients, the appropriate building envelope design schemes were discussed in different climates. At last, the regression model evaluations consisting of the simulation evaluations and the actual case evaluations were performed to verify the feasibility and accuracy of the regression models. The error rates are within±5% in the simulation evaluations and within±15% in the actual case evaluations. It is believed that the regression models developed in this paper can be used to estimate the energy consumption of office buildings in different climates when various building envelope designs are considered.

关键词: regression model     energy consumption     building envelope     office building     different climates    

Crystal modification of rifapentine using different solvents

Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 65-69 doi: 10.1007/s11705-009-0302-6

摘要: Rifapentine crystals with different habits were prepared by recrystallization from selected solvents, such as methanol, ethanol, chloroform, and acetic acid. Scanning electron microscopy, X-ray powder diffractometry, infrared spectrometry, and differential scanning calorimetry were used to investigate the physicochemical characteristics of the prepared crystals. The comparative dissolution behaviors of the newly developed crystals and of rifapentine without being treated were also studied. Results show that the newly developed crystals were different from each other with respect to physical properties but were identical chemically. Needle-shaped crystals were obtained from methanol, ethanol, and chloroform solvents, and the block-shaped crystals were obtained from acetic acid solvent. X-ray diffraction spectra and differential scanning calorimetry investigation on those developed crystals clearly indicate that rifapentine has different crystal structure modification. When the crystal was obtained from acetic acid, the change of crystal habit was originated from the crystal structure modification. The dissolution rate of newly developed crystals was found to be higher than that of rifapentine without being treated. However, the modified crystal obtained from acetic acid shows the lower dissolution rate than crystals obtained from other solvents.

关键词: identical     scanning calorimetry     different     comparative dissolution     structure modification    

标题 作者 时间 类型 操作

Nucleation and growth mechanism of cefodizime sodium at different solvent compositions

Xinwei ZHANG, Shudong ZHANG, Xiaodan SUN, Zequn YIN, Quanjie LIU, Xiwen ZHANG, Qiuxiang YIN

期刊论文

Bioengineering protection mechanism of city rock slope and its laboratory test

Desong JIANG, Minghua ZHAO, Chong JIANG,

期刊论文

Not asthma, but GERD: case report

WANG Zhonggao

期刊论文

Ecological compensation mechanism for urban green land and its application in Shanghai, China

WANG Yan, DING Xiaowen, QIAN Longxia, WANG Hongrui

期刊论文

Numerical analysis of rotating stall characteristics in vaneless diffuser with large width-radius ratio

GAO Chuang, GU Chuangang, WANG Tong, DAI Zhengyuan

期刊论文

Abnormal expression of c-Myc in human bronchial epithelial cells malignantly transformed by anti-BPDE

FU Juan, JIANG Yiguo, CHEN Xuemin

期刊论文

A review on different theoretical models of electrocaloric effect for refrigeration

期刊论文

Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

ZHOU Hongbo, CHEN Zhuchang

期刊论文

Characterization and catalytic properties of mesoporous CuO/SBA-16 prepared by different impregnation

DONG Yongli, YUAN Fulong, ZHU Yujun, ZHAO Lina, CAI Zhicheng

期刊论文

Effect of different high viscosity modifiers on rheological properties of high viscosity asphalt

期刊论文

Enhanced performance of oxygen vacancies on CO adsorption and activation over different phases of ZrO

期刊论文

Untargeted metabolomic analysis of pregnant women exposure to perfluorooctanoic acid at different degrees

期刊论文

Effectiveness of tertiary treatment processes in removing different classes of emerging contaminants

期刊论文

Multiple regression models for energy consumption of office buildings in different climates in China

Siyu ZHOU, Neng ZHU

期刊论文

Crystal modification of rifapentine using different solvents

Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,

期刊论文