Numerical investigation of film forming characteristics and mass transfer enhancement in horizontal polycondensation kettle

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%.

Film forming systems for topical and transdermal drug delivery

Skin is considered as an important route of administration of drugs for both local and systemic effects. The effectiveness of topical therapy depends on the physicochemical properties of the drug and adherence of the patient to the treatment regimen as well as the system’s ability to adhere to skin during the therapy so as to promote drug penetration through the skin barrier.Conventional formulations for topical and dermatological administration of drugs have certain limitations like poor adherence to skin, poor permeability and compromised patient compliance.For the treatment of diseases of body tissues and wounds, the drug has to be maintained at the site of treatment for an effective period of time. Topical film forming systems are such developing drug delivery systems meant for topical application to the skin, which adhere to the body, forming a thin transparent film and provide delivery of the active ingredients to the body tissue. These are intended for skin application as emollient or protective and for local action or transdermal penetration of medicament for systemic action. The transparency is an appreciable feature of this polymeric system which greatly influences the patient acceptance.In the current discussion, the film forming systems are described as a promising choice for topical and transdermal drug delivery. Further the various types of film forming systems (sprays/solutions, gels and emulsions) along with their evaluation parameters have also been reviewed.

Application of Ceramic Film as Means of Lubrication for Forming of TiSheet in a Highly Localized Deformation Process

Incremental forming is a novel die-less sheet forming process. There is a need for special means to retain lubricant at the tool/sheet interface during forming. To fulfillthe stated aim, a porous ceramic film was developed on pure Ti substrate, and it was done through an electrochemical depsition process known as plasma electrolytic oxidation. The film with preferred pore size could be realized after several attempts by varying the processing parameters. In order to characterize the film, a variety of tests including rnicrostructure, film-substrate bond strength and tribological properties tests were conducted. On-job performance of the film was also examined by forming Ti components employing a range of forming conditions. It was found that the proposed method of lubrication was effective, and the plasma eletrolytic oxidation process can be employed to fabricate films on pure Ti sheet to provide means of lubrication during incremental forming.

Evaluation of blank film forming polymeric dispersions based on Eudragit RL 30D and RS30D for transdermal drug delivery

The first approved transdermal drug delivery system in the United States in 1979 is a scopolamine patch for treatment of motion sickness. Transdermal drug delivery system has many advantages over oral route such as it is useful for vomiting and unconscious patients. It can avoid first pass metabolism by the liver. It is non-invasive way and self-administered system compared to injections. The film forming polymeric solutions are a novel transdermal drug delivery system. This system consists of an active drug, film forming polymer, plasticizer.

Simulation of bulk metal forming processes using one-step finite element approach based on deformation theory of plasticity

The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/strain distributions.This approach was implemented to minimize the approximated plastic potential energy derived from the total plastic work and the equivalent external work in static equilibrium,for incompressibly rigid-plastic materials,by FE calculation based on the extremum work principle.The one-step forward simulations of compression and rolling processes were presented as examples,and the results were compared with those obtained by classical incremental FE simulation to verify the feasibility and validity of the proposed method.

Influence of Acetic Acid on Dynamic Behavior of Hydrolazation and Film Forming of Organosilane

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.

THE STABILITY INVESTIGATION OF FERROELECTRIC SrBi_2Ta_2O_9 THIN FILMS ANNEALED IN FORMING GAS

The hysteresis loop changes of ferroelecric SrBi_2 Ta_2 O_9 (SBT) thin films(330nm) us the temperature of forming gas (5 percent hydrogen+95 percent nitrogen) annealing weremeasured when the annealing time was 1min and 10min. The selected annealing temperature was at 100deg C,200 deg C 250 deg C, 300 deg C, 350 deg C,400 deg C and 450 deg C, respectively. Our resultsshowed that the ferroelectric properties were easily destroyed and the leakage current changedabruptly when the SBT thin films were in their ferroelectric phase (<270 deg C). The space chargesat the grain boundary may take an important role' in absorption polarity molecular hydrogen when theSBT thin films were in the ferroelectric phase. The oxygen recovery experiments were also performedand investigated in this work.

Development of Film Forming Agent HN-1 and Its Application in Drilling Fluid

Borehole instability and reservoir damage had become the international technical problems of petroleum exploration and development of complicated area, and the water of drilling fluid invading borehole wall and petroleum reservoir was the main cause of borehole instability and reservoir damage. In order to prevent the water of drilling fluid invading borehole wall and petroleum reservoir, domestic and foreign scholars recently put forward the technology of ultra-low permeable drilling fluid. Film forming agent was the key treating agent of ultra-low permeable drilling fluid, the film forming agent (HN-1) was developed, which did not affect properties of the drilling fluid and could decrease the filter loss of drilling fluid applied in Enping 24-2 oil field. Based on this research, ultra-low permeable drilling fluid could be applied to Enping 24-2 oil field. By the methods of testing ultra-low permeable drilling fluid properties, the drilling fluid invasion sand-bed depth, drilling fluid high temperature/high pressure (HTHP) sand-bed filter loss, the pressure-bearing ability of rock core and the ability of reservoir protection were studied. By synergistic effect, HN-1 containing the organic silicate and natural fiber polymer modified by organic amine prevented the liquid and solids in drilling fluid invading reservoir, decreased drilling fluid invasion sand-bed depth and drilling fluid HTHP sand-bed filter loss, improved the pressure-bearing ability of rock core and the ability of reservoir protection. The drilling fluid could decrease reservoir damage to the maximal degree, and it offered efficiency guarantee for exploitation Enping 24-2 oil field.

The Synthesis and Film Forming Properties of Unsymmetrical Phthalocyanine Bearing One Crown Ether Void

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

Forming Stages of Polycrystalline TiN Films Depending on the Nitrogen Concentration in Mixed Gas

The influence of nitrogen concentration in mixed gas on temperature conditions, structure and phase composition of the TiN film deposited by arc spraying has been investigated. By electron microscopic investigations and X-ray diffraction phase analysis was recognized forming stages and structuring process of the film with main cubic phase (111) TiN. It was discovered that forming stages and process of structuring of ion-plasma TiN films are affected by both film temperature and its rate of heating.

Rheological property of low-damage,ideal packing,film-forming amphoteric/sulfonation polymer drilling fluids

Low-permeability dense reservoirs,including micro-fractured reservoirs,are commonly characterized by high content of clay substances,high original water saturation,high sensitivity to invasive fluids,high capillary pressure,complicated structure and anisotropic,high flow-resistance and micro pore throats etc,.Generally they also have lots of natural micro fractures,probably leading to stress sensibility.Main damaging factors in such reservoirs are water-sensibility and water-blocking caused by invasive fluids during drilling and production operations.Once damaged,formation permeability can rarely recovered.Numerous studies have shown that damaging extent of water-blocking ranges from 70% to 90%.Main damaging mechanisms and influencing factors of water-blocking were systematically analyzed.Also some feasible precaution or treating approaches of water-blocking were put forward.In a laboratory setting,a new multi-functional drilling fluid composed mainly of amphion polymer,sulfonation polymer,high effectively preventive water-blocking surfactants,ideal packing temporary bridging agents(TBA) and film-forming agents,etc.,were developed.New low-damage drilling fluids has many advantages,such as good rheological properties,excellent effectiveness of water-blocking prevention,good temporary plugging effect,low filtration and ultra-low permeability(API filtration≤5 mL,HTHP filtration≤10 mL,mud cake frictional coefficient≤0.14,permeability recovery>81%),can efficiently prevent or minimize damage,preserve natural formation and enhance comprehensive development-investment effect in TUHA Jurassic dense sandstone reservoir formation with low-permeability,the only one developing integrated condense gas field.Some references can be provided to similar reservoir formations.

Challenges in the Development of Film-Forming Additives for Lithium Ion Battery: A Review

Electrolytes additives are ubiquitous and indispensable in all electrochemical devices. In this sense, the principle and the classification of film-forming additives for lithium ion secondary batteries are described. The film formation mechanism and research progress of the pyrazole derivatives, organic halogenide, esters and derivatives, boron compounds and inorganic compounds are introduced. Emphasis is focused on the principles and film-forming mechanisms of each additive. The development of film-forming additives is forecasted and prospected.

The Use of an Innovative Film-Forming Wound Dressing in the Treatment of Radiation Dermatitis during Concomitant Chemotherapy

There is currently no consensus regarding the management of acute cutaneous reactions emerging from a concurrent treatment of radio-and chemotherapy, the goal of this case study series is to provide scientific evidence based on clinical practice regarding the efficacy of a film-forming wound dressing for patients receiving combined cancer therapy, in particular examples where the reactions are expected to be intense. In all the described cases, management of acute skin reactions allowed the cancer therapy to be finalized, instead of being interrupted due to an increase in the severity of the reactions. It has been shown in the current literature that the lack of compliance with treatment plans correlates with poorer clinical outcome. Evidence from the cases presented suggest that the studied dressing is safe and efficacious in the treatment and the prevention of acute cutaneous reactions arising from combined cancer therapy.

Film-Forming Systems in Topically Administered Pharmaceutical Formulations

The skin is the most extensive and outermost organ in the body and can be greatly exploited both from the point of view of alternative routes of systemic drug delivery and treatment of dermatological diseases. Because of its main function as a barrier against harmful external agents, it also becomes a barrier to drug administration, but there are strategies to reduce this limitation of this promising route of administration. The development of polymer-based film-forming formulations is extensively studied for this purpose, since the formation of a film on the skin increases the contact time of the drug, for this being characterized as a controlled release reservoir system. There are a multitude of possible polymers to compose these formulations and their choice must be made according to the purpose of each application. This work, therefore, aims to study the state of the art of film forming systems for topical application of pharmaceutical formulations.

Formation mechanism of pulse current anodized film on AZ91D Mg alloy

The kinetics of forming process of pulse current anodized film on AZ91D Mg alloy was studied by the voltage-time and thickness-time curves.The surface morphology,structure,elemental constitution and valences of the anodic films were analyzed by SEM,EDS,XPS and XRD respectively.The results show that the film-forming process can be divided into four stages.Formation of a dense layer before sparking is the first stage.Formation of a porous layer accompanied with slight sparking is the second stage.The third stage is characterized by fast growth of the porous layer accompanied with more intensive sparking.The fourth stage starts after the sparking process becomes even more vigorous and the pores become large.

Cyclodextrin-Modified Film Dosage Forms for Oral Candidiasis Treatment

Oral candidiasis is a common disease in patients with dry mouth. In this study, film dosage forms (FD) incorporating miconazole nitrate, an antifungal agent, were prepared with water-soluble polysaccharide and cyclodextrin (CD). The dissolution profiles of the drug from the FDs were investigated in limited dissolution medium. Soft films were obtained from sodium alginate containing 0.5% α-CD, β-CD, or γ-CD. Most FDs were easy to handle, though the film tearing resistance was lower than that of CD-free FDs. Addition of CD to the FD accelerated the drug dissolution rate. Interestingly, this phenomenon was also observed in FDs prepared with pullulan. In contrast, acceleration of the drug dissolution rate was not observed when CD polymer was added to the base solution. The initial drug dissolution rate was controllable by the amount of CD added to the FD. Therefore, FDs prepared with these materials are useful to treat oral candidiasis in patients with dry mouth syndrome.

Preparation and Characteristics of Film Dosage Form Natural Polysaccharides

We investigated preparation of film dosage form (FD) from natural polysaccharides using the casting method without organic solvents, heating or pH control. Ferulic acid (FA) and catechin were employed as model compounds incorporated in the FD, and the release profile of each compound from the form was investigated in the limited medium. Film formation was affected by the addition of the model compound to the polysaccharide solution. Rigid FD was obtained with 2% low-molecular-weight alginate (L-ALG;thickness, 65 μm), and it hardened after the addition of 0.5% polygalacturonic acid, although the thickness of the film did not change. The FDs immediately released the model compound, and the forms dissolved in phosphate-buffered saline. FD modification did not affect the FA release rate except in the early stage. FD would be a useful dosage form, especially for preventing or treating localized problems in the oral cavity.

Development of Film Dosage Forms Containing Miconazole for the Treatment of Oral Candidiasis

Film dosage forms (FDs) containing miconazole (MCZ) for the treatment of oral candidiasis were prepared using water-soluble polysaccharides, and the dissolution profiles of MCZ from the FDs were investigated. In addition, the forms were modified by the addition of a surface active agent to accelerate the drug dissolution rate. Circular films incorporating MCZ were obtained using each polysaccharide. Most FDs were easy to handle and resistant to tearing. No diffraction peaks were observed in the X-ray diffractograms of FDs. FDs prepared with sodium alginate or pullulan immediately swelled and disintegrated in aqueous medium, whereas MCZ incorporated in the FD gradually dissolved. A marked acceleration in the MCZ dissolution rate was observed when FD was prepared with polysaccharide containing a surfactant. These results confirmed that modified FDs are useful for treating localized conditions in the oral cavity, such as oral candidiasis, and that FDs can simplify the administration of drugs to patients.

Features of the formation and nanostructure of the film with the basic hexagonal phase TiN_0.3by arc evaporation

Forming and nanostructuring processes of TiN film by electric arc evaporation under the conditions of the reactive nitrogen gas deficit in the gas mixture (30%) have been investigated. The results of a technological experiment, electron microscopic examination, X-ray diffraction phase analysis and mechanical testing of the film revealed that a significant increase in ion density and mobility leads to deterioration of the formation temperature conditions, structural and phase changes in TiN film and change of the main cubic phase (111)TiN on a hexagonal (101)TiN0.3. In the end repeated decrease of the the film microhardness with (101)TiN0.3 was caused not only by erosion of the film, but also because of change in the processes of its formation and nanostructuring in comparison with similar processes of the film with (111)TiN.

Effective tool design of three-rank form as precision removal-process of ITO thin-films

A new effective tool design of three-rank form of electroremoval was present using a precision recycle system offering faster performance in removing the indium-tin-oxide(ITO) thin-films on color filter surface of displays. Higher electric power is not required since the three-rank form tool is adopted as a feeding mode to reduce the response area. The low yield of ITO persists throughout the entire semiconductor production process. By establishing a recycle process of ultra-precise removal of the thin-film nanostructure, defective products in the optoelectronic semiconductors industry can be effectively recycled, decreasing both production costs and pollution. A 5th generation TFT-LCD was used. The design features of the removal processes for the thin-films and the tool design of three-rank form were of major interest. For the precision removal processes, a pulsed current can improve the effect of dreg discharge and contributes to the achievement of a fast workpiece (displays' color filter) feed rate, but raises the current rating. High flow velocity of the electrolyte with a high rotational speed of the tool electrodes elevates the ITO removal effect. A displays' color filter with a fast feed rate is combined with enough electric power to provide highly effective removal. A small thickness of the rank and a small arc angle of the negative-electrode correspond to a higher removal rate for ITO-film. An effective three-rank form negative-electrode provides larger discharge mobility and better removal effect. It only needs a short period of time to remove the ITO easily and cleanly.