Top PDF In-situ control system for atomization

In situ control system for atomization

In-situ control system for atomization

Melt atomizing apparatus comprising a melt supply orifice for supplying the melt or atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray.
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In Situ Monitoring for Fatigue Crack Detection using Control System and Image Processing

In Situ Monitoring for Fatigue Crack Detection using Control System and Image Processing

specimen for detection of fatigue crack is proposed in this paper. The system is designed to alarm the user as soon as it detects the crack. The purpose is achieved by building a control system using a camera and Raspberry Pi controller. The crack is identified by an image processing algorithm. The dimensions of crack are also measured automatically by the algorithm. The aim of project is to alarm the user about the presence of fatigue crack and display the dimensions of the crack. Use of controller for image processing instead of computer makes the system compact.
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Opposing chemokine gradients control human thymocyte migration in situ

Opposing chemokine gradients control human thymocyte migration in situ

Our study presented 2 complementary models to examine human thymocyte migration within a living 3-dimensional thymic stromal environment: the human→mouse system allowed for manipula- tion of stromal cell environments using genetically engineered mice, and the human→human system provided information about the human thymic microenvironment. Together, these systems offer a unique opportunity to study the molecular signals that direct human T cell behavior and development, as well as interspecies crosstalk, and should help to inform the development of improved in vivo humanized mouse models. Moreover, immune-modulatory drugs, including small-molecule antagonists to chemokine recep- tors, such as AMD3100, represent an emerging therapeutic modal- ity (53). We foresee that the thymic slice model may serve as a pre- clinical tool to investigate the effect of immune-modulatory drugs on human thymocyte development. This tool may be of particular relevance to the treatment of infants and children, whose peripheral T cell pool is predominantly shaped by recent thymic emigrants. Methods
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FORMULATION AND EVALUATION OF IN SITU GELLING OCULAR SYSTEM OF OFLOXACIN

FORMULATION AND EVALUATION OF IN SITU GELLING OCULAR SYSTEM OF OFLOXACIN

The sterile formulation were taken into laminar airflow. Sterile formulation was removed from the vials by help of syringe. the solution was passed through the membrane filter of 0.45µm size with the help of vacuum pump. after filtration, the filter paper was removed from funnel and it was cut into two half. One half was dropped into bacterial media (Fluid thioglycolate) and other half was drooped in the fungal media (Soyabean casein digest). The media were kept for incubation for 14 days at 37 0 C. Both the, media were observed every day for any microbial contamination and compared with a positive and negative control. [10]
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Microwave system for in situ curing of concrete repair

Microwave system for in situ curing of concrete repair

The Proportional Integral Derivative (PID) controller (Minorsky 1922) is a control loop feedback mecha- nism. It has become the most commonly used closed-loop controller in all types of industrial con- trol systems due to its simplicity and excellent per- formance (Astrom & Murray 2010). In a PID con- troller its input signal is the error e(t) between a user defined set point r(t) and a measured plant/process variable y(t) as shown in Equation 1. The terms plant and process refer to the object or the process that is being controlled by the PID controller. In the case of MCure system the process is the microwave heating of the repair patch and the error e(t) is the difference between the measured temperature y(t) and the target temperature r(t) (40 to 45 o C) (Mangat et al. 2015, Mangat et al.2016.). The output signal u(t) of the PID controller in time t-domain is given by Equation 2.
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Modeling and control of in-situ decontamination of large water resources

Modeling and control of in-situ decontamination of large water resources

The idea developed in this paper is completely different: facing a contaminated water resource, an alternative could be to pump water from the reservoir, to treat it in dedicated and appropriate WWTPs (depending on the chemicals to be removed from water), and to release decontaminated water to the reservoir. This implies the use of a continuous water treatment system, typically in a (set of) process tank(s) called bioreactor(s). Coupling a continuous decontamination process with the hydrodynamics of the water resource brings some issues, and especially the following ones.

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Spray and Atomization of Diesel and its Alternative Fuels from a
Single Hole Injector Using a Common Rail Fuel Injection System.

Spray and Atomization of Diesel and its Alternative Fuels from a Single Hole Injector Using a Common Rail Fuel Injection System.

The injection system is illustrated in Figure 1. A first generation common rail fuel system is built to control and maintain the fuel at a given constant injection pressure (up to 1350 bar). The fuel stored in a fuel tank is delivered by a low pressure pump and passes through a fuel filter (Caterpillar 1R-0751). The filtration media inside the filter is able to remove 98 percent of any particles larger than 2 𝜇𝜇𝜇𝜇 in the fuel. The flitted fuel is transported to the high pressure pump (BOSCH CR/CP1S3/R70/10-16S) which is driven by a 3 phases, 2 horsepower AC motor (GE K1496, maximum speed: 1725 rpm) with timing belt and pulleys. An idler pulley was provided to enhance the tension of belt. The common rail (BOSCH 0-445-214-122) has a pressure sensor (BOSCH 07-05-08-03135) providing the pressure values inside the common rail. A specially machined single holed injector nozzle with a diameter of 100 𝜇𝜇𝜇𝜇 is used in this work. The vibration caused by operating the AC motor and high pressure pump shook the equipment while conducting experiment, therefore, an injector holder is added to the tip of injector to make injector remains stable during the experiment.
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Laboratory-generated primary marine aerosol via bubble-bursting and atomization

Laboratory-generated primary marine aerosol via bubble-bursting and atomization

by the reduced inertial forces linked to plunging water jets of small dimensions. Available evidence suggests that the op- timum system to reach the oceanic bubble lifetimes would be the generation of a large-scale plunging water jet in large volume tanks (>100 l) as those employed by Facchini et al. (2008). This would allow the recirculation of high water flows (e.g. 20 lpm, Facchini et al., 2008) and the generation of deep plumes with high speed water jets (e.g. >6 m s −1 , Chanson et al., 2002) and thus, produce bubble plumes with depth penetrations >0.5 m and high void fractions which re- tard the bubbles motion to the surface. These high speed jets can be produced by adjusting the nozzle diameter and height over water. As both the void fractions and the size of the bubbles generated by large scale plunging jets are ex- pected to be representative of those of oceanic plumes (Chan- son et al., 2004), the generation of plume depths >0.5 m by a plunging water jet of these characteristics would ensure pro- ducing bubbles with lifetimes of the order of those in real plumes. This type of generator is, nevertheless, only useful when large amounts of sample are available, thus they are ap- propriate for in situ measurements with seawater. Due to the characteristics of our experiments, specifically regarding the limitations in the production of organic-enriched seawater with phytoplankton cultures, this type of large experimental system is not suitable for our study. Nevertheless, within this limitation, physical models of reduced dimensions have been demonstrated to be useful for studying the process of for- mation and evolution of oceanic bubble plumes and aerosol properties on a scaled basis (Leifer et al., 2007; Cipriano and Blanchard, 1981; Sellegri et al., 2006; Hultin et al., 2009). Implications derived from the limited lifetime in the labora- tory systems, regarding the adsorption of organics by rising bubbles, are analyzed in the next section.
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In Situ Gelling System - An Overview

In Situ Gelling System - An Overview

Xyloglucan is a polysaccharide derived from tamarind seeds and it is composed of a (1→4)-β-D-glucan backbone which has (1→6)-α-D-xylose branches that are partially substituted by (1→2)-β-D-galactoxylose 46 . Xyloglucan forms thermo responsive gels in water, under certain conditions. When xyloglucan is partially degraded by β-galactosidase, the resultant product exhibits thermally reversible gelation in dilute aqueous solutions. Such behavior does not occur with native xyloglucan. Gelation is only possible when the galactose removal ratio exceeds 35% 47 . The transition temperature is inversely related to polymer concentration 48 and the galactose removal ratio. For example, the sol–gel transition of xyloglucan was shown to decrease from 40 °C to 5 °C when the galactose removal ratio increased from 35 to 58%. Xyloglucan formulations were assessed for ocular delivery of pilocarpine; using Poloxamer 407 as a positive thermosensitive control. The 1.5 wt. % xyloglucan formulation enhanced the miotic response to a degree similar to that of a 25 wt. % Poloxamer 407 gel 49 . In comparison with gellan and alginate, in the oral administration of cimetidine, xyloglucan gels appear to be the system with the widest application because its gelation does not require the presence of cations, as in the case of alginate, and its use is not restricted by the charged nature of the drug, as in the case of gellan 50 . Xyloglucan gels have also been investigated for ocular delivery of pilocarpine and timolol 51,52 . The in situ gelling formulations were consistently more effective than aqueous buffer solutions while the rapid gelation was essential in preventing the loss of drug by drainage from the eye. Xyloglucan gels have also been used as vehicles for a sustained release of percutaneous formulations of non-steroidal anti-inflammatory drugs 53 .
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Studies on in situ gelling system for better ocular drug therapy.

Studies on in situ gelling system for better ocular drug therapy.

The drug was tested in Dexamethasone induced ocular hypertensive rabbits (n= 6). In the Dexamethasone responder rabbits, topical ocular administration of drugs in situ gel [forskolin (0.25 mg; 25 µl of 1% w/v suspension), Timolol (0.125 mg; 25 µl of 0.5% w/v solution), Pilocarpine (0.5 mg; 25 µl of 2% w/v solution), Betaxolol (0.125 mg; 25 µl of 0.5% w/v solution), Dorzolamide (0.5 mg; 25 µl of 2% w/v solution)] lowered the IOP (Fig. 7.107, 7.109, 7.111, 7.113, 7.115). Administration of drug suspension/ solution [forskolin (0.5 mg; 50 µl of 1% w/v suspension), Timolol (0.125 mg; 25 µl of 0.5% w/v solution), Pilocarpine (0.5 mg; 25 µl of 2% w/v solution), Betaxolol (0.125 mg; 25 µl of 0.5% w/v solution), Dorzolamide (0.5 mg; 25 µl of 2% w/v solution)] had a small but significant effect on the IOP. A statistically significant (P< 0.01) reduction was observed in A3P4FN, A3P4TM, A3P4BH, A3P4PN, A3P4DH containing drug at 1 to 12 h after drug treatment. While in PL18FN, PL18TM, PL18BH, PL18PN, PL18DH AA03FN, AA03TM, AA03BH, AA03PN and AA03DH the reduction were observed for 1-11 h. Thus in situ gels were showing a long and a higher response, indicative of a sustained and better absorption of the drug. ∆IOP is reported as the mean (±S.E.M.) for n = 6 (Fig. 7.108, 7.110, 7.112, 7.114, 7.116). An experiment was also performed where only the vehicles were instilled into the treated eye, keeping the other eye as control. No significant change in IOP was found between the control and the treated eye, indicating the absence of any vehicle effect. Moreover, the contralateral eyes in all the experiments showed no significant drop in the IOP. Interestingly, when in situ gel was administered to the same Dexamethasone responder animals 13 days later for three consecutive days, it still generated comparable ocular hypotensive effects, suggesting that acute desensitization did not occur. Again, ocular or systemic side effects of drugs were not detected.
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In situ analysis for intelligent control

In situ analysis for intelligent control

this study include two unsupervised clustering algorithms, in- tended to identify the important distinguishing characteristics of bodies of points within a data sample. The use of two dif- ferent approaches allows us to exploit the strengths of each of the approaches to provide a robust identification of interesting phenomena in the water-column. Specifically, we use a self- organising map (SOM) to construct an accurate classification of HS-2 Hydroscat data and an Inductive Monitoring System (IMS) clusterer which is effective at identifying data that lies outside the learned range of original training data. Clustering techniques have been applied to hydroscat data in the past [6], [14], but our work represents the first attempt to use clustered data to support in situ control of a scientific instrument in the ocean sciences.
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PATIENT COMPLIANT OCULAR IN SITU GELLING SYSTEM OF AZITHROMYCIN DIHYDRATE

PATIENT COMPLIANT OCULAR IN SITU GELLING SYSTEM OF AZITHROMYCIN DIHYDRATE

solution, is based on Durasite ® drug delivery technology evolved from cross linked polyacrylic acid [6] But highly viscous solutions and gels lack accuracy of dosing and ease of administration. Lachrymation and hazy vision associated with preformed hydrogels may be avoided by using in situ activated gel forming systems, which are viscous liquids that upon exposure to physiological conditions change into a gel or solid phase in the cul de sac upon its instillation into the eye. In situ gelation approach combines advantages of both solutions and gels, such as accuracy of dose and ease of administration of the former and prolonged precorneal retention of the latter. [7,8]
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A NOVEL OPHTHALMIC DRUG DELIVERY SYSTEM: IN SITU GEL

A NOVEL OPHTHALMIC DRUG DELIVERY SYSTEM: IN SITU GEL

Rathapon A, et al.,(2011), optimized and evaluated Pluronic F127-based thermoresponsive diclofenac sodium ophthalmic in-situ gels. They were prepared by cold method and investigated their physicochemical properties like sol–gel transition temperature, gelling capacity, rheological properties and effect of concentration of polymer i.e., carbopol 940, Pluronic- F68. An optimized formulation was selected and investigated its physicochemical properties before and after autoclaving, eye irritation potency in rabbits. In vivo ophthalmic absorption was performed in rabbits. It was found that physicochemical properties of diclofenac sodium in-situ gels were affected by formulation compositions. Increment of Pluronic-F127 content decreased sol–gel transition temperature of the products while increase in Pluronic-F68 concentration tended to increase sol–gel transition temperature. In this study, Carbopol 940 did not affect sol–gel transition temperature but it affected transparency, pH, and gelling capacity of the products. The optimized formulation exhibited sol–gel transition at 32.6±1.1°C with pseudoplastic flow behavior. 19 Sirish V, et al., (2010), prepared and evaluated novel in-situ ocular gelling system (Thermo-reversible gelling systems) of Ketorolac tromethamine. These gelling systems involve the use of Poloxamer as thermo reversible polymer and Methyl cellulose as release retardant. They evaluated the formulations for clarity, pH measurement, gelling capacity, drug content estimation, rheological study, in vitro drug release, ocular irritation studies (as per Draize test) and ex-vivo corneal permeation studies using isolated goats cornea. The developed formulations showed sustained release of drug for upto 5 hrs. 20
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Log-normal melt pulsation in close-coupled gas atomization

Log-normal melt pulsation in close-coupled gas atomization

Close-Coupled Gas Atomization (CCGA) is the production technique of choice when fine (5-50 µm), highly spherical, metal powders are required. In principle CCGA is straightforward, high pressure gas jets impinging upon a molten metal stream are used to disrupt the stream, breaking it into a spray of fine droplets. Liquid metal is delivered down the central bore of the nozzle, wherein it wets the nozzle tip (a process termed pre-filming, which is itself dependent upon the gas flow conditions) and is stripped off the circumferential edge of the nozzle by the gas. However, the complex interaction between the high velocity gas and the metal results in a turbulent, and often chaotic, flow with the result being that the details of the process are far from well understood. Consequently, early work into gas atomization focused on empirical correlations between median particle size and process parameters [1, 2] such as gas pressure, gas flow rate and melt flow rate. The most widely quoted of these empirical relationships is that due Lubanska [1], which correlates particle size with (1+G) -1/2 , where G is the gas:metal mass ratio.
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Development of a Modular In-Situ Oil Analysis Prognostic System

Development of a Modular In-Situ Oil Analysis Prognostic System

Hardware: Determination of wear and contaminant elements in the oil (by elemental analysis) is accomplished using a specially designed X-ray fluorescence spectrometer. The XRF system uses a small amount of suitable radionuclide in a well- sealed fail proof container as a source of X-rays. The system is designed to operate using very little power. XRF analysis can detect and quantitate wear metals such as iron, copper, chromium, aluminum, silver and lead as well as elements commonly used in lubricant additive packages such as zinc and molybdenum.

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IN SITU GEL FORMING INJECTABLE DRUG DELIVERY SYSTEM

IN SITU GEL FORMING INJECTABLE DRUG DELIVERY SYSTEM

In general, sorbitan monostearate organogels have a very short half-life at the injection site. This may be attributed to the diffusion of water molecules within the gelled structure which results in the subsequent disruption of the networked structure due to the emulsification of the gel surface. The same group has also reported the development of a sorbitan monostearate based organogels which has shown sustained delivery of a model antigen and radiolabelled bovine serum albumin after intra-muscular administration of the same in mice. The results indicated the probable use of the formulation as depot. L alanine based injectable in situ forming organogels may be used for the delivery of labile macromolecular bioactive agents. These in situ forming organogels may be used for sustained delivery of bioactive agents after the same is being administered within the body. Various L-alanine derivates, viz. N-stearoyl l- alanine (m) ethyl esters, may be used to immobilize vegetable and synthetic oil in the presence of a hydrophilic solvent. These gels are thermoreversible in nature. The gel-to-sol transition of the L-alanine based organogels was dependent on the concentration of the gelator and the nature of the solvent 16, 17 .
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Optimization of in situ gelling system for nasal administration of celecoxib

Optimization of in situ gelling system for nasal administration of celecoxib

the 15% pluronic gel containing plain drug. This may be due to the lack of complete gelation of the system in presence of cyclodextrin, which could interfere with the micelle aggregation of pluronic as well as its hard sphere ation mechanism. The gelling effect of pluronic was overcome by the solubilization effect of cyclodextrin which also added as the synergistic effect with the surfactant property of pluronic in solution, ultimately leading to released. As the complexation ratio was varied, drug release upto 100 % at the end of 6 hours could be observed in 1:3 ratio complex in gel formulation as compared to 61% drug release observed from the same complex filled in capsule. This highest percentage of drug release is more significant, since greater improvement in the bioavailability can be achieved within 6h for this hydrophobic drug, through both the
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Liquid Column Deformation and Particle Size Distribution in Gas Atomization

Liquid Column Deformation and Particle Size Distribution in Gas Atomization

The current study investigates the initial stage of tur- bulent mixing in a close coupled atomizer, which is as- sumed to take place within a finite convergence region; this region constitutes a crucial subtlety of a flexible mathematical model for the atomization of liquid metals already presented elsewhere [25]. The model - covering both primary and secondary atomization - is applicable to any liquid//gas system and is based on the formation of sinusoidal traveling waves along the surface of a liquid [26,27]. Estimation of the convergence region diameter is of great importance to modeling of the gas flow [28], as it determines the Mach number, static temperature and sonic velocities of the gas inducing break up of the liquid column.
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Formulation and Evaluation Of PH Triggered In Situ Gelling System of Levofloxacin

Formulation and Evaluation Of PH Triggered In Situ Gelling System of Levofloxacin

The in situ gelling system provides longer contact time and sustained delivery of the drug, hence decrease in frequency of administration and improved patient compliance are the major advantages. The ocular conjunctivitis caused by various micro organism causes permanent conjunctival damages, corneal ulceration, systemic infections. The role of topical quinolones reserved principally for severe bacterial conjunctivitis. 22

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Formulation and Evaluation of PH Triggered In Situ Gelling System of Levofloxacin

Formulation and Evaluation of PH Triggered In Situ Gelling System of Levofloxacin

33. Jawahar.N. et a1., designed poly (D,L-Lactide-co-glycolide) (PLGA) nanoparticles of ramipril by nanoprecipitation method using tribloere polymeric stabilizer (pluronic F-68). The particles were characterized for drug content, particle size, and particle morphology. In vitro release studies were performed by dialysis bag diffusion technique. The prepared nanoparticles were placed in the dialysis bag and immersed in 50ml of phosphate buffer saline (PBS) PH 7.4. The entire system was kept at 37°± 0.5°C with continuous magnetic stirring at 200 rpm. The amount of drug dissolved was determined with uv-spectrophotometry at 207nm.
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