The process of producing high viscosity polyester by transesterification polycondensation needs to adjust the operating conditions and equipment structure of pre-polycondensation kettle and final polycondensation kett...The process of producing high viscosity polyester by transesterification polycondensation needs to adjust the operating conditions and equipment structure of pre-polycondensation kettle and final polycondensation kettle to realize process intensification.In view of this,the fluid volume function method of computational fluid dynamics numerical simulation was used to investigate the film formation and surface renewal characteristics of horizontal polycondensation kettle under different operating conditions,including viscosity,rotating speed and liquid height.The results show that the viscosity and rotating speed were positively correlated with the film area and surface renewal in the pre-polycondensation stage.However,increasing the viscosity by several orders of magnitude in the final polycondensation kettle,the larger the film area and film thickness,but the overall surface renewal of the disk decreased.Therefore,a hexagonal hole disk is designed.By comparison,it is found that the film is more uniform,the surface update frequency is higher,and the power consumption can be reduced by more than 20%.展开更多
The influence of acetic acid on dynamic behavior of hydrolazation and film forming of an expoxy-silane compound (y-GPS) was investigated by conductivity meter, IR and AFM. The experimental results show that there is...The influence of acetic acid on dynamic behavior of hydrolazation and film forming of an expoxy-silane compound (y-GPS) was investigated by conductivity meter, IR and AFM. The experimental results show that there is an optimal pH value(pH=4-5) for hydrolysis of silane solution, and with the prolongation of hydrolytic time, the promotion of acetic acid on the hydrolyzation of silane solution become more obvious. During the adsorption and film forming process, acetic acid could promote the formation of Si-O-Fe bond, which activates hydroxyl group of silanol unit and facilitates this hydroxyl group to react with adjacent silanol unit forming linear condensation polymers.展开更多
The synthesis of phthalocyanines bearing one crown ether macrocycle and three alkoxyl chains is described. They form stable monolayers and can be employed for the preparation of multilayer films by the Langmuir-Bloget...The synthesis of phthalocyanines bearing one crown ether macrocycle and three alkoxyl chains is described. They form stable monolayers and can be employed for the preparation of multilayer films by the Langmuir-Blogett technique. The orientations of the molecules in the film were affected by alkali metal ions in the subphase. lt is suggested that a kind of 'sandwich' dimer was formed in the film induced by potassium ions展开更多
Over the recent few decades,many groups of formulation scientists are concentrating on rapid release dosage forms in oral cavity.Among all fast release dosage forms,orodispersible films are successful to attract pharm...Over the recent few decades,many groups of formulation scientists are concentrating on rapid release dosage forms in oral cavity.Among all fast release dosage forms,orodispersible films are successful to attract pharmaceutical industry due to ease of formulation and extension patent life.Films are popular in patients too because of quick onset and user friendliness of dosage form.From the beginning,solvent casting has been selected as method of choice for manufacturing of orodispersible films.Solvent casting has been proved as a benchmark technology because of ease in product development,process optimization,process validation and technology transfer to production scale despite of some drawbacks like more number of unit operations involved and consumption of large quantity of solvents with controlled limits of organic volatile impurities in final formulation.The application of hot-melt extrusion(HME)in the pharmaceutical industry is consecutively increasing due to its proven innumerable advantages like solvent free continuous process with fewer unit operations and better content uniformity.Very few development activities has been initiated in the field of hot melt extruded orodispersible films so far.This extensive review covers detailed discussion of heavy duty industrial extruders,selection of downstream equipments,selection of excipients,common problems found in formulations and their remedies.Successive part of review addresses identification of critical quality attributes,quality target profile of product,criticality in selection of process parameters and material for substantial simulation in laboratory scale and production for successful technology transfer.展开更多
In a previous paper, we have reported the relationship between the crystallite orientation of the evaporated film of copper phthalacyanine (PcCu) (α-form) and the incident angle of molecular beam at 10-5 torr. In...In a previous paper, we have reported the relationship between the crystallite orientation of the evaporated film of copper phthalacyanine (PcCu) (α-form) and the incident angle of molecular beam at 10-5 torr. In this paper, we shall show some research results about vacuum effects on the crystal forms and the morphology of the evaporat-展开更多
Three novel fluorinated cationic surfactants were prepared by adopting perfluoro-2-methy1-2-pentene as raw substrate. The as-obtained fluorinated cationic surfactants exhibited excellent surface properties, all of the...Three novel fluorinated cationic surfactants were prepared by adopting perfluoro-2-methy1-2-pentene as raw substrate. The as-obtained fluorinated cationic surfactants exhibited excellent surface properties, all of them can reduce the surface tension of water to below 20.00mN/m at the critical micelle concentrations (CMC). The incorporation of SDS, AOS, APG or LAB into 2-(4-(3,3,4,4,5,5,5-heptafluoro- 2,2-bis(trifluoromethyl)pentyl)benzamido)-N,N-dimethylethana-mine oxide 4a could generate much lower CMC and surface tension value at the CMC than individual 4a. Especially, the surface tension values of that combined APG/4a can be reduced to 17.31 mN/m. The excellent surface activities and their remarkable compatibility to various types of hydrocarbon surfactants make them as sustainable alternatives to PFOA (perfluorooctanoic acid, C7F15CO2H) and PFOS (perfluorooctane sulphonate, C8F17SO3X, with X = K, Na, H).展开更多
b Département de Physique, Ecole Polythechnique Fédérale de Lausanne, EPFL, Lausanne, Switzerland c Department of Chemistry, Tsinghua University, Beijing 100084, China An excellent hole-transpor...b Département de Physique, Ecole Polythechnique Fédérale de Lausanne, EPFL, Lausanne, Switzerland c Department of Chemistry, Tsinghua University, Beijing 100084, China An excellent hole-transport material, 1,3-diphenyl-5-(9-phenanthryl)-2-pyrazoline (DPPhP) for OLEDs was studied. This compound not only offers high glass transition temperature (T g=96 ℃), good film forming ability, and high HOMO energy level, but also displays excellent hole-transport property. The electroluminescent device with a simple structure of ITO/DPPhP (60 nm)/AlQ (60 nm)/LiF (0.8 nm)/Al shows an external quantum efficiency as high as 1.6%.展开更多
Derived from dry powder coating of metals, electrostatic powder coating for pharmaceuticals is a technology for coating drug solid dosage forms. In this technology, coating powders, containing coating polymers, pigmen...Derived from dry powder coating of metals, electrostatic powder coating for pharmaceuticals is a technology for coating drug solid dosage forms. In this technology, coating powders, containing coating polymers, pigments, and other excipients, are directly sprayed onto the surface of the solid dosage forms through an electrostatic gun without using any organic solvent or water. The deposited coating powders are further cured to form a coating film. Electrostatic powder coating technology has many advantages compared to other pharmaceutical coating methods. It can eliminate the limitations caused by the organic solvent in solvent coating such as environmental issues and health problems. And electrostatic powder coating technology also surpasses aqueous coating due to its shorter processing time and less energy consumption, leading to a lower overall cost. Furthermore, the utilization of electrical attraction can promote the movement of coating powders towards the substrate, leading to an enhanced coating powder adhesion and coating efficiency, which make it more promising compared to other dry coating technologies. The objective of this review is to summarize the coating principles, apparatus, and formulations of different electrostatic powder coating technologies, giving their advantages and limitations and also analyzing the future application in the industry for each technology展开更多
基金the financial support of the National Key Research and Development Program of China(2020YFA0710202,2018YFC0808805)。
文摘The process of producing high viscosity polyester by transesterification polycondensation needs to adjust the operating conditions and equipment structure of pre-polycondensation kettle and final polycondensation kettle to realize process intensification.In view of this,the fluid volume function method of computational fluid dynamics numerical simulation was used to investigate the film formation and surface renewal characteristics of horizontal polycondensation kettle under different operating conditions,including viscosity,rotating speed and liquid height.The results show that the viscosity and rotating speed were positively correlated with the film area and surface renewal in the pre-polycondensation stage.However,increasing the viscosity by several orders of magnitude in the final polycondensation kettle,the larger the film area and film thickness,but the overall surface renewal of the disk decreased.Therefore,a hexagonal hole disk is designed.By comparison,it is found that the film is more uniform,the surface update frequency is higher,and the power consumption can be reduced by more than 20%.
基金Funded by the National Natural Science Foundation of China(No.50801057)Hubei Provincial Natural Science Foundation ( No.2008CDB263)the Research Foundation for Outstanding Young Teachers,China University of Geosciences(Wuhan) (No. CUGQNL0803)
文摘The influence of acetic acid on dynamic behavior of hydrolazation and film forming of an expoxy-silane compound (y-GPS) was investigated by conductivity meter, IR and AFM. The experimental results show that there is an optimal pH value(pH=4-5) for hydrolysis of silane solution, and with the prolongation of hydrolytic time, the promotion of acetic acid on the hydrolyzation of silane solution become more obvious. During the adsorption and film forming process, acetic acid could promote the formation of Si-O-Fe bond, which activates hydroxyl group of silanol unit and facilitates this hydroxyl group to react with adjacent silanol unit forming linear condensation polymers.
文摘The synthesis of phthalocyanines bearing one crown ether macrocycle and three alkoxyl chains is described. They form stable monolayers and can be employed for the preparation of multilayer films by the Langmuir-Blogett technique. The orientations of the molecules in the film were affected by alkali metal ions in the subphase. lt is suggested that a kind of 'sandwich' dimer was formed in the film induced by potassium ions
文摘Over the recent few decades,many groups of formulation scientists are concentrating on rapid release dosage forms in oral cavity.Among all fast release dosage forms,orodispersible films are successful to attract pharmaceutical industry due to ease of formulation and extension patent life.Films are popular in patients too because of quick onset and user friendliness of dosage form.From the beginning,solvent casting has been selected as method of choice for manufacturing of orodispersible films.Solvent casting has been proved as a benchmark technology because of ease in product development,process optimization,process validation and technology transfer to production scale despite of some drawbacks like more number of unit operations involved and consumption of large quantity of solvents with controlled limits of organic volatile impurities in final formulation.The application of hot-melt extrusion(HME)in the pharmaceutical industry is consecutively increasing due to its proven innumerable advantages like solvent free continuous process with fewer unit operations and better content uniformity.Very few development activities has been initiated in the field of hot melt extruded orodispersible films so far.This extensive review covers detailed discussion of heavy duty industrial extruders,selection of downstream equipments,selection of excipients,common problems found in formulations and their remedies.Successive part of review addresses identification of critical quality attributes,quality target profile of product,criticality in selection of process parameters and material for substantial simulation in laboratory scale and production for successful technology transfer.
文摘In a previous paper, we have reported the relationship between the crystallite orientation of the evaporated film of copper phthalacyanine (PcCu) (α-form) and the incident angle of molecular beam at 10-5 torr. In this paper, we shall show some research results about vacuum effects on the crystal forms and the morphology of the evaporat-
基金supported by the National Natural Science Foundation of China (No. 2167020782)the Science and Technology Commission of Shanghai Municipality (No. 15DZ2281500)
文摘Three novel fluorinated cationic surfactants were prepared by adopting perfluoro-2-methy1-2-pentene as raw substrate. The as-obtained fluorinated cationic surfactants exhibited excellent surface properties, all of them can reduce the surface tension of water to below 20.00mN/m at the critical micelle concentrations (CMC). The incorporation of SDS, AOS, APG or LAB into 2-(4-(3,3,4,4,5,5,5-heptafluoro- 2,2-bis(trifluoromethyl)pentyl)benzamido)-N,N-dimethylethana-mine oxide 4a could generate much lower CMC and surface tension value at the CMC than individual 4a. Especially, the surface tension values of that combined APG/4a can be reduced to 17.31 mN/m. The excellent surface activities and their remarkable compatibility to various types of hydrocarbon surfactants make them as sustainable alternatives to PFOA (perfluorooctanoic acid, C7F15CO2H) and PFOS (perfluorooctane sulphonate, C8F17SO3X, with X = K, Na, H).
文摘b Département de Physique, Ecole Polythechnique Fédérale de Lausanne, EPFL, Lausanne, Switzerland c Department of Chemistry, Tsinghua University, Beijing 100084, China An excellent hole-transport material, 1,3-diphenyl-5-(9-phenanthryl)-2-pyrazoline (DPPhP) for OLEDs was studied. This compound not only offers high glass transition temperature (T g=96 ℃), good film forming ability, and high HOMO energy level, but also displays excellent hole-transport property. The electroluminescent device with a simple structure of ITO/DPPhP (60 nm)/AlQ (60 nm)/LiF (0.8 nm)/Al shows an external quantum efficiency as high as 1.6%.
文摘Derived from dry powder coating of metals, electrostatic powder coating for pharmaceuticals is a technology for coating drug solid dosage forms. In this technology, coating powders, containing coating polymers, pigments, and other excipients, are directly sprayed onto the surface of the solid dosage forms through an electrostatic gun without using any organic solvent or water. The deposited coating powders are further cured to form a coating film. Electrostatic powder coating technology has many advantages compared to other pharmaceutical coating methods. It can eliminate the limitations caused by the organic solvent in solvent coating such as environmental issues and health problems. And electrostatic powder coating technology also surpasses aqueous coating due to its shorter processing time and less energy consumption, leading to a lower overall cost. Furthermore, the utilization of electrical attraction can promote the movement of coating powders towards the substrate, leading to an enhanced coating powder adhesion and coating efficiency, which make it more promising compared to other dry coating technologies. The objective of this review is to summarize the coating principles, apparatus, and formulations of different electrostatic powder coating technologies, giving their advantages and limitations and also analyzing the future application in the industry for each technology