Solid-State Variation of Troglitazone Drug Substance by Using a Different Recrystallization Method

Abstract

Rapid and slow crystallization methods (A and B) were applied for troglitazone, an equal mixture of four stereoisomers. Differences in the powder x-ray diffractometry patterns and hygroscopic patterns were observed among the samples crystallized by these methods, suggesting that troglitazone has solid-state variation. In this article, troglitazone recrystallized by method A was evaluated to clarify its structural characteristics and physical property. The crystal structure of predried troglitazone recrystallized by method A was proved to be a dihydrate. By drying, it changed reversibly to an anhydrate, which is the same structure as the RS/SR form, keeping the same enantiomer ratio. The solubility of the troglitazone by method A higher than that by method B at all enantiomer levels. But making the troglitazone amorphous equalized the enantiomeric solubilities of the substances by both methods as well as increased the intrinsic solubilities. Troglitazone by both methods was proved to be stable and retained the ratio of the stereoisomers.     

PVA聚合度和醇解度对涤棉混纺纱上浆的影响

研究PVA的聚合度和醇解度对涤棉混纺纱浆纱质量的影响.应用PVA-0588、PVA-0599、PVA-1788、PVA-1799等不同醇解度、不同聚合度的PVA对纯棉纱和涤棉混纺纱进行了浆纱试验.结果表明:聚合度和醇解度不同,PVA的成膜性、水溶性及对纤维的粘附力会有很大差异;部分醇解PVA具有较好的吸湿性和水溶性;PVA-1788对于涤棉混纺纱上浆具有更好的浆纱性能.     

Investigating the effects of humidity and salt crystallisation on medieval masonry

An investigation of the effects of humidity and salt crystallisation on medieval masonry has been undertaken at the parish church of Walpole St Andrew, Norfolk, with the intention of establishing a relationship between changes in environmental conditions and levels of stone decay. Masonry within the church has been contaminated with sodium chloride salts, which are undergoing cycles of crystallisation/dissolution in response to fluctuations in relative humidity corresponding to the equilibrium relative humidity of the salt. The effects of these cycles have been determined by a combination of gravimetric analysis, ion chromatography, and qualitative assessment of deposited material. Appropriate remedial action, based on a combination of desalination techniques and environmental control, is put forward for discussion.     

大米麦芽糊精的性质及应用

介绍了大米麦芽糊精的制备，粘度、吸湿性等方面的独特性，以及大米麦芽糊精在食品、医药、造纸、建筑等行业的应用。     

环境湿度对含TNT卷制半可燃药筒燃烧性能影响研究

为研究环境湿度对以TNT为粘结剂的卷制型半可燃药筒定容燃烧特性的影响规律,采用称重法研究了药筒的吸湿特性,并对在不同环境湿度下吸湿饱和的试样进行密闭爆发器实验。研究结果表明：含TNT卷制半可燃药筒的吸湿能力随环境的相对湿度增加而增加;并且卷制半可燃药筒火药力和燃速压力指数整体呈增大趋势,燃烧最大压强、燃烧结束时间、余容以及燃速系数则呈现下降趋势。     

2号岩石粉状铵梯油炸药结块硬化的原因分析

从原材料水分、装药温度、半成品吸湿性与成品水分,在不同温度下的成品储存等方面,探讨２号岩石粉状铵梯油炸药结块硬化的原因。     

Effects of Spray-Drying Conditions on the Physicochemical Properties of Blackberry Powder

The purpose of this work was to study the effects of spray-drying conditions on the physicochemical characteristics of blackberry powder using a central composite rotatable design. Inlet air temperature (140–180°C) and maltodextrin concentration (5–25%) were employed as independent variables. Moisture content, hygroscopicity, anthocyanin retention, color, powder morphology, and particle size were analyzed. A higher inlet air temperature significantly increased the hygroscopicity of the powder, decreased its moisture content, and led to the formation of larger particles with smooth surfaces. Powders produced with higher maltodextrin concentrations were less hygroscopic, slightly lighter and less red, and had a lower moisture content. Anthocyanin retention was mainly affected by drying temperature due to the heat sensitivity of the pigment. The optimal processing conditions were an inlet air temperature of 140–150°C and maltodextrin concentration of 5–7%. Overall, these results indicate that good quality powders can be obtained by spray drying, with potential applications for the food industry.     

Effect of Maltodextrin Addition during Spray Drying of Tomato Pulp in Dehumidified Air: II. Powder Properties

This work investigates the effect of maltodextrin addition on the main powder properties during spray drying of tomato pulp in dehumidified air. A pilot-scale spray dryer was employed for the spray-drying process. The modification made to the original design consisted in connecting the spray dryer inlet air intake to an absorption air dryer. 21 DE, 12 DE, and 6 DE maltodextrins were used as drying agents. Tomato pulp was spray dried at inlet air temperatures of 130, 140, and 150°C and (tomato pulp solids)/(maltodextrin solids) ratios of 4.00, 1.00, and 0.25. The tomato powders were analyzed for rheological properties, moisture content, bulk density, solubility, hygroscopicity, and degree of caking. It was found that maltodextrin addition improved powder hygroscopicity, caking, and solubility, whereas it deteriorated slightly its moisture content and density. In addition, analysis of experimental data yielded correlations between powder properties and the above-mentioned variable operating conditions. Regression analysis was used to fit a full second-order polynomial, reduced second-order polynomials, and linear models to the data of each of the properties evaluated. F values for all reduced and linear models with an R ² ≥ 0.70 were calculated to determine if the models could be used in place of full second-order polynomials.     

Image Analysis,Homogenization, Numerical Simulation and Experiment as Complementary Tools to Enlighten the Relationship between Wood Anatomy and Drying Behavior

Abstract

This paper has been written for a special issue devoted to the works done in France in the field of drying. Therefore, it aims, through numerous examples, to show the spirit which initiates and guides the research work of the Forest Products Unit at ENGREF : how more and more microscopic information can be included in the study of the drying process ?

Two steps are involved :

?microscopic observation and experiments to predict the macroscopic properties

?use of the macroscopic properties (the previous step + experiments carried our at the macroscopic scale) to predict the drying behavior.

In this approach, each prediction comes from a model, that means assumptions, formulations, calculations and then validation.

Several tools (image analysis, homogenization, measurement of microscopic and macroscopic properties, numerical simulation of heat and mass transfer, refined drying experiments) are used to study the drying of wood.     

硝酸铵的吸湿性研究

介绍了硝酸铵的吸湿机理,防止硝酸铵吸湿的手段以及吸湿性和包覆效果的表征方法,并对防止硝酸铵吸湿的各种手段进行分析。