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Research progress on hydrothermal dissolution and hydrolysis of lignocellulose and lignocellulosic waste

Yan ZHAO, Wenjing LU, Jiajun CHEN, Xiangfeng ZHANG, Hongtao WANG

《环境科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 151-161 doi: 10.1007/s11783-013-0607-z

摘要： Ethanol production from lignocellulosic waste has attracted considerable attention because of its feasibility and the generation of valuable products. Previous studies have shown that pretreatment and hydrolysis are key processes for lignocellulose conversion. Hydrothermal process is a promising technique because of its efficiency to break down the lignocellulosic structures and produce fermentable hexoses. Most studies in this field have therefore focused on understanding these processes or optimizing the parameters, but commonly reported low yields of fermentable hexoses. The inability to produce high yields of fermentable hexoses is mainly attributed to inadequate information on the conversion mechanisms of lignocellulose, particularly the reaction rules of dissolution, which is a limiting step in the entire conversion process. This paper critically reviewed the progress done in the research and development of the hydrothermal dissolution and hydrolysis of lignocellulose. Principles, processes, and related studies on separate dissolution and asynchronous hydrolysis of lignin, hemicellulose, and cellulose are presented. Potential research prospects are also suggested.

关键词： lignocellulosic waste     hydrothermal conversion     separate dissolution     asynchronous hydrolysis     mechanism    

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Improved dissolution and anti-inflammatory effect of ibuprofen by solid dispersion

null

《医学前沿（英文）》 2012年 第6卷 第2期   页码 195-203 doi: 10.1007/s11684-012-0189-3

摘要：

The purpose of this study was to improve the dissolution rate and anti-inflammatory effect of ibuprofen by a solid dispersion (SD) method. Initial screening was developed based on drug solubility in carriers in the liquid state to select a suitable water-soluble carrier system for the preparation of SDs. The dissolution of ibuprofen in urea was higher than in PEG4000 or mannitol. Thus, urea was selected as the carrier for the preparation of SDs. SDs were characterized in terms of dissolution, differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. Solid dispersion-based (SDBT) and conventional (CT) tablets were prepared by the wet granulation method. The anti-inflammatory effect of SDBT was evaluated using the mouse ear edema test with xylene. In vitro release results indicated that the ibuprofen dissolution rate was improved by the SD. SD characterization results suggested that ibuprofen partly precipitates in crystalline and amorphous forms after SD preparation and that ibuprofen and urea do not interact. SDBT displayed more significant anti-inflammatory effects than CT. The dissolution rate and anti-inflammatory effect of ibuprofen were significantly enhanced by the ibuprofen-urea SD.

关键词： ibuprofen     solid dispersion     physical mixture     dissolution     anti-inflammatory effect    

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Cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles of Fe dissolution

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1586-8

摘要：

● nZVI, S-nZVI, and nFeS were systematically compared for Cd(II) removal.

关键词： Nano zero valent iron     Sulfided zero valent iron     FeS     Cd(II) immobilization     Fe dissolution    

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Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 384-398 doi: 10.1007/s11705-020-1928-7

摘要： The jet-flow high shear mixer (JF-HSM) is a new type of intensified equipment with special configurations of the rotor and the stator. The mass transfer property and power consumption were studied in the solid-liquid system for a series of JF-HSMs involving different configuration parameters, such as rotor diameter, rotor blade inclination, rotor blade bending direction, stator diameter, and stator bottom opening diameter. The flow characteristics were examined by computational fluid dynamic simulations. Results indicate that the turbulent power consumption of the JF-HSM is affected by the change in rotor blade inclination and stator bottom opening. With the increase in the shear head size and the change in the rotor into a backward-curved blade, the solid-liquid mass transfer rate can be remarkably increased under the same input power. Dimensionless correlations for the mass transfer coefficient and power consumption were obtained to guide the scale-up design and selection of such a new type of equipment to intensify the overall mixing efficiency.

关键词： jet-flow high shear mixer     solid particle dissolution     power consumption characteristics     CFD Simulation    

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Nonlinear finite element analysis of short-limbed wall

Zhi ZHANG, Qian GU, Shaomin PENG, Quanzhi CAI

《结构与土木工程前沿（英文）》 2009年 第3卷 第2期   页码 125-130 doi: 10.1007/s11709-009-0025-2

摘要： Combined with the actual project, this paper carries out a nonlinear finite element analysis on 2 groups, 6 short-limbed shear walls, through the finite element calculation software ANSYS. The stress-strain relation of the models, and the effects of the type of sections and the axial compression ratios on the models can be obtained, providing a reference for future design.

关键词： short-limbed wall (SLW)     nonlinear finite element     separate model     axial compression ratios    

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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    

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Dynamic characteristics of a shrouded blade with impact and friction

Xumin GUO, Jin ZENG, Hui MA, Chenguang ZHAO, Lin QU, Bangchun WEN

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 209-226 doi: 10.1007/s11465-019-0566-6

摘要： A simplified computational model of a twisted shrouded blade with impact and friction is established. In this model, the shrouded blade is simulated by a flexible Timoshenko beam with a tip-mass, and the effects of centrifugal stiffening, spin softening, and Coriolis force are considered. Impact force is simulated using a linear spring model, and friction force is generated by a tangential spring model under sticking state and a Coulomb friction model under sliding state. The proposed model is validated by a finite element model. Then, the effects of initial gap and normal preload, coefficient of friction, and contact stiffness ratio (the ratio of tangential contact stiffness to normal contact stiffness) on system vibration responses are analyzed. Results show that resonant peaks become inconspicuous and impact plays a dominant role when initial gaps are large between adjacent shrouds. By contrast, in small initial gaps or initial normal preloads condition, resonant speed increases sharply, and the optimal initial normal preloads that can minimize resonant amplitude becomes apparent. Coefficient of friction affects the optimal initial normal preload, but it does not affect vibration responses when the contact between shrouds is under full stick. System resonant amplitude decreases with the increase of contact stiffness ratio, but the optimal initial normal preload is unaffected.

关键词： twisted shrouded blade     dynamic analysis     impact     friction     separate–stick–slip motion    

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Oral product input to the GI tract: GIS an oral product performance technology

Gordon L. Amidon, Yasuhiro Tsume

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 516-520 doi: 10.1007/s11705-017-1658-7

摘要： The patient receives a pharmaceutical product, not a drug. The pharmaceutical products are formulated with a drug, an active ingredient to produce the maximum therapeutic effect after oral absorption. Therefore, it is the product we must optimize for the patients. In order to assure the safety and efficacy of pharmaceutical products, we need an predictive tool for oral product performance in patients. Currently, we are a surprisingly long way from accomplishing that objective. If the 20th century was the ‘age of the drug’, i.e., the ‘magic bullet’, the 21st century must become the ‘age of the guided missile’, i.e., the delivery system, including the form of the active pharmaceutical ingredient (API) (‘drug’). The physical form of the drug and the delivery system must be optimized to maximize the therapeutic benefits of pharmaceutical products for humans. Oral immediate release (IR) dosage forms cannot be optimal for all drugs or likely even any drugs (APIs). Still, the formulation of pharmaceutical products has to be optimized for patients. But how do we optimize oral delivery of drugs? It is usually through ‘trial and error’, in humans! We need a better way to optimize the oral dosage forms. We have suggested to select different dissolution methodologies for this optimization based on BCS Subclasses. In this article, we present the predicted drug dissolution profile of ketoconazole as a model drug from our laboratory utilizing a gastrointestinal simulator (GIS), which is an adaptation of the ASD system. GIS consists of three chambers representing stomach, duodenum, and jejunum, to create the human gastrointestinal tract-like environment and enable the control the gastric emptying rate. This dissolution system allows the monitoring of the drug dissolution phenomena and the observation of the supersaturation and the precipitation of pharmaceutical products, which is useful information to predict dissolution of pharmaceutical products. This system can provide the actual input needed to accurately predict the input into the systemic circulation required by many of the absorption prediction packages available today.

关键词： GIS     in vivo predictive dissolution     ketoconazole     BCS subclassification     supersaturation    

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某型飞机双座弹射轨迹仿真分析

王伟,封文春,林贵平

《中国工程科学》 2010年 第12卷 第1期   页码 86-90

摘要：

以HTY-8座椅为原型，建立了具有轨迹发散作用的仿真模型，通过仿真，比较分析了发散火箭在不同冲量和不同弹射条件下对弹射轨迹的影响。仿真结果表明，在零速度或速度较低的弹射条件下，采用发散火箭是必要的。在中高速弹射条件下，由于前后座椅弹射具有一定的时间差，X方向轨迹离散，前后座椅弹射轨迹发散，发散火箭的作用并不明显，尚需进一步分析人椅分离后先弹射的座椅的运动轨迹。在不利姿态弹射条件下，横滚时发散火箭作用并不明显，俯冲时则能够起到轨迹发散作用。

关键词： 弹射座椅     双座弹射     轨迹发散     弹射仿真    

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Modeling of specific structure crystallization coupling with dissolution

Yuanhui JI, Hongliang QIAN, Chang LIU, Xiaohua LU, Xin FENG, Xiaoyan JI,

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 52-56 doi: 10.1007/s11705-009-0301-7

摘要： In this paper, the research framework for specific structure crystallization modeling has been proposed in which four steps are required in order to investigate the rigorous crystallization modeling by thermodynamics. The first is the activity coefficient model of the solution, the second is Solid-Liquid equilibrium, the third and fourth are the dissolution and crystallization kinetics modeling, respectively. Our investigations show that the mechanisms of complex structure formation and microphase transition can be analyzed by combining the dissolution and crystallization kinetics modeling. Moreover, the formation mechanism of the porous KCl has been analyzed, which may provide a reference for the porous structure formation in the advanced material synthesis.

关键词： structure crystallization     activity coefficient     reference     KCl     dissolution    

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Dissolution and enzymatic hydrolysis of casein micelles studied by dynamic light scattering

LIU Rui, QI Wei, SU Rongxin, ZHANG Yubin, JIN Fengmin, HE Zhimin

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 123-127 doi: 10.1007/s11705-007-0023-7

摘要： The effects of temperature, ionic strength, and enzymatic hydrolysis on the average hydrodynamic radius () of casein micelles in phosphate buffer were studied by using dynamic light scattering. The results showed that the average value of casein micelles decreased irreversibly during the heating, decreased with the increase of ionic strength in lower ionic strength solution (less than 0.05 mol/L), but opposite in higher ionic strength solution (above 0.1 mol/L). The value of casein increased rapidly during the process of enzymatic hydrolysis, and the structural model of casein micelles in the enzymatic hydrolysis process was also proposed, i.e. the casein micelle changed from compact sphere into unfolded and regularly flocky peptides.

关键词： compact     strength     temperature     regularly flocky     heating    

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Construction of nitrogen-doped carbon cladding LiMnO film electrode with enhanced stability for electrochemically selective extraction of lithium ions

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2050-2060 doi: 10.1007/s11705-023-2343-7

摘要： Reducing the dissolution of Mn from LiMn2O4 (LMO) and enhancing the stability of film electrodes are critical and challenging for Li+ ions selective extraction via electrochemically switched ion exchange technology. In this work, we prepared a nitrogen-doped carbon cladding LMO (C-N@LMO) by polymerization of polypyrrole and high-temperature annealing in the N2 gas to achieve the above purpose. The modified C-N@LMO film electrode exhibited lower Mn dissolution and better cyclic stability than the LMO film electrode. The dissolution ratio of Mn from the C-N@LMO film electrode decreased by 42% compared to the LMO film electrode after 10 cycles. The cladding layer not only acted as a protective layer but also functioned as a conductive shell, accelerating the migration rate of Li+ ions. The intercalation equilibrium time of the C-N@LMO film electrode reached within an hour during the extraction of Li+ ions, which was 33% less compared to the pure LMO film electrode. Meanwhile, the C-N@LMO film electrode retained evident selectivity toward Li+ ions, and the separation factor was 118.38 for Li+ toward Mg2+ in simulated brine. Therefore, the C-N@LMO film electrode would be a promising candidate for the recovery of Li+ ions from salt lakes.

关键词： LiMn2O4     lithium extraction     surface coating     cyclic stability     Mn dissolution    

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标题 作者 时间 类型 操作

Research progress on hydrothermal dissolution and hydrolysis of lignocellulose and lignocellulosic waste

Yan ZHAO, Wenjing LU, Jiajun CHEN, Xiangfeng ZHANG, Hongtao WANG

期刊论文

Improved dissolution and anti-inflammatory effect of ibuprofen by solid dispersion

null

期刊论文

Cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles of Fe dissolution

期刊论文

Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

期刊论文

Nonlinear finite element analysis of short-limbed wall

Zhi ZHANG, Qian GU, Shaomin PENG, Quanzhi CAI

期刊论文

Crystal modification of rifapentine using different solvents

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

期刊论文

Dynamic characteristics of a shrouded blade with impact and friction

Xumin GUO, Jin ZENG, Hui MA, Chenguang ZHAO, Lin QU, Bangchun WEN

期刊论文

Oral product input to the GI tract: GIS an oral product performance technology

Gordon L. Amidon, Yasuhiro Tsume

期刊论文

某型飞机双座弹射轨迹仿真分析

王伟,封文春,林贵平

期刊论文

Modeling of specific structure crystallization coupling with dissolution

Yuanhui JI, Hongliang QIAN, Chang LIU, Xiaohua LU, Xin FENG, Xiaoyan JI,

期刊论文

Dissolution and enzymatic hydrolysis of casein micelles studied by dynamic light scattering

LIU Rui, QI Wei, SU Rongxin, ZHANG Yubin, JIN Fengmin, HE Zhimin

期刊论文

Construction of nitrogen-doped carbon cladding LiMnO film electrode with enhanced stability for electrochemically selective extraction of lithium ions

期刊论文