Ultrafine grained materials through mechanical processing: an assessment

In this paper severe plastic deformation (SPD) and friction stir processing/ welding are examined. The structural changes due to SPD are reflected in improved mechanical properties. Advantages of SPD are pointed out. Within the SPD technique, a number of approaches are possible, e.g., equi-channel angular pressing/extrusion, high pressure torsion, accumulative roll bonding/fold - roll process, reciprocating extrusion - compression, cyclic close die forging, repetitive corrugation and straightening. Analyses available are elementary and often assume uniform stress and strain distribution. These processes are easily adapted to suit standard metal working equipment fitted with inexpensive devices and tools. However, scaling up the processes to handle large billets and achieve large tonnage production is difficult. In the near future, medium and small-scale industrial production only is likely. Friction stir process, a solid state technique for joining similar or dissimilar materials of equal or different thickness, has some key metallurgical, environmental and energy benefits. It is already being considered for applications in aerospace and automotive industries. Significant improvements in surface properties and superplastic flow have been established in friction stir processed materials. Velocity of tool movement and power input needed for fast rotation of the tool are the major variables. Since significant temperature rise is there during processing, in a proper analysis, the boundary conditions arising from thermal and mechanical constraints have to be satisfied simultaneously, which is an extremely difficult. A few key issues have to be addressed before large-scale production can be attempted. An integral approach that takes into account the total system of material, design, mechanics and component forming is likely to lead to industrially relevant solutions

Teamwork self-efficacy and employee satisfaction: a sequential framework to build employee cohesion

The occupational psychological health of the employees is affected by the behavior of their peers in the workplace. To reduce psychological stress and improve the well-being of employees, organizations are focusing on developing coherence through various human resources practices. In the current business scenario, it is crucial to address psychological stress by building employee cohesion. The aim of this study is to analyze how employees’ teamwork self-efficacy influences group cohesion through employee satisfaction. This study followed a quantitative approach to test the data, which comprises 228 information technology (IT) professionals, working in top IT companies in India. This study used a partial least squares structural equation modeling approach to test the hypothesis. The results revealed that employees’ teamwork self-efficacy is not directly influencing employee cohesion, whereas it has a significant positive influence on an employee’s cohesion only with the mediation effect of an employee’s satisfaction. Predominantly, an employee’s extrinsic satisfaction has a greater influence on the aforesaid relationship than an employee’s intrinsic satisfaction. The results of this study suggest human resources development practitioners place more emphasis on delivering motivational benefits and providing collaboration-oriented interventions that strengthen teamwork self-efficacy, since these factors may directly affect employee cohesion given that a large portion of the respondents were young adults

Ultrafine grained materials through mechanical processing: An assessment

In this paper severe plastic deformation (SPD) and friction stir processing/ welding are examined. The structural changes due to SPD are reflected in improved mechanical properties. Advantages of SPD are pointed out. Within the SPD technique, a number of approaches are possible, e.g., equi-channel angular pressing/extrusion, high pressure torsion, accumulative roll bonding/fold - roll process, reciprocating extrusion – compression, cyclic close die forging, repetitive corrugation and straightening. Analyses available are elementary and often assume uniform stress and strain distribution. These processes are easily adapted to suit standard metal working equipment fitted with inexpensive devices and tools. However, scaling up the processes to handle large billets and achieve large tonnage production is difficult. In the near future, medium and small-scale industrial production only is likely. Friction stir process, a solid state technique for joining similar or dissimilar materials of equal or different thickness, has some key metallurgical, environmental and energy benefits. It is already being considered for applications in aerospace and automotive industries. Significant improvements in surface properties and superplastic flow have been established in friction stir processed materials. Velocity of tool movement and power input needed for fast rotation of the tool are the major variables. Since significant temperature rise is there during processing, in a proper analysis, the boundary conditions arising from thermal and mechanical constraints have to be satisfied simultaneously, which is an extremely difficult. A few key issues have to be addressed before large-scale production can be attempted. An integral approach that takes into account the total system of material, design, mechanics and component forming is likely to lead to industrially relevant solutions

Perancangan Fasilitas Rehabilitasi Mental untuk Penderita Depresi

Depresi merupakan gangguan emosi yang ditandai oleh perasaan sedih dan berubahnya pola hidup yang berujung dengan pemikiran untuk menyakitidiri sendiri atau mengakhiri hidup. Beberapa riset menyatakan bahwa penderita depresi bertambah pesat setiap tahunnya yang kemudian berbandingterbaik dengan ketersediaan fasilitas yang ada. Tempat rehabilitasi di Indonesia masih berpusat di Rumah Sakit jiwa dimana lingkungan yang disediakan lebih memenuhi aspek fungsional. Dilihat dari sisi psikologis, faktor lingkungan berperan penting dalam proses penyembuhan. Hal ini yangseringkali diabaikan sehingga proses terapi menjadi tidak maksimal. Dalam studi perancangan ini bertujuan menciptakan lingkungan yang ideal yangmendukung proses rehabilitasi dengan penggunaan unsur-unsur interior. Dalam proses studi perancangan penulis menemukan beberapa kesulitanyaitu bagaimana menerjemahkan konsep lingkungan ideal yang berbentuk abstrak menjadi elemen interior. Sehingga penulis melakukan survey untukmengetahui metode pengaplikasian warna dan pencahayaan, serta elemen - elemen interior lainnya

Formulation and evaluation of sustained release microspheres of rosin containing aceclofenac

Aceclofenac was microencapsulated using rosin by o/w emulsion solvent evaporation technique. The effect of three formulation variables including the drug:polymer ratio, emulsifier (polyvinyl alcohol) concentration and organic solvent (dichloromethane) volume were examined. The prepared batches were characterized for microspheres particle size distribution, encapsulation efficiency and in vitro release behavior. The study reveals that drug:polymer ratio had a considerable effect on the entrapment efficiency, however particle size distribution of microspheres was more dependent on the volume of dichloromethane and polyvinyl alcohol concentration rather than on the drug: polymer ratio. Drug, polymer concentrations were varied to obtain optimum release profile for sustaining the action of the drug

Analisis Penentuan Jenis Fluida Pendorong Menggunakan Metode Material Balance Berdasarkan Nilai Recovery Factor Pada Lapangan “Arl” Petrochina International Jabung Ltd

Lapangan “ARL” telah berproduksi sejak bulan Januari 2001. Diketahui bahwa mekanisme pendorong yang bekerjapada reservoir ini merupakan water drive. Untuk meyakinkan hasil tersebut, maka dilakukan pengkajian ulang denganmenggunakan metode yang berbeda sebagai bahan validasi. Berdasarkan analisa mekanisme pendorong yang telahdilakukan dengan menggunakan metode material balance, reservoir lapangan ini benar memiliki jenis Water DriveMechanism sebagai mekanisme pendorongnya dimana tenaga pendorong terbesarnya didominasi oleh air, yaitu WaterDrive Index (WDI) 74,1%, Untuk meyakinkan hasil analisis dengan menggunakan metode material balance tersebut,maka dilanjutkan dengan perhitungan recovery factor dengan metode decline curve.Nilai recovery factor yang didapat dari hasil perhitungan ini adalah 37,58% dengan prediksi kumulatif minyak sampaiSeptember 2013 ini adalah sebesar 21.432 MBBL dan Remaining Reserve (RR) sebesar 11.357 MBBL, makaLapangan “ARL” ini masih menyisakan cadangan (EUR) sebesar 32.789 MBBL.yang secara teori membenarkanbahwa tingkat perolehan berkisar 35-75% merupakan kisaran efisiensi perolehan minyak pada jenis water drivereservoir

Design and Evaluation of Matrix Diffusion Controlled Transdermal Patches of Diltiazem Hydrochloride

Se desarrolló un sistema matricial de tipo dispersivo para la administración transdérmica de clorhidrato de Diltiazem usando diferentes proporciones de colofonia con Eudragit RL PM y polivinil pirrolidona. El parche preparado con colofonia y polivinil pirrolidona no era transparente y muestra una distribución irregular de polivinil pirrolidona, lo que puede ser debido al carácter hidrófi lo de ésta. Se investigó el efecto de los polímeros sobre las propiedades tecnológicas; es decir, la liberación del fármaco, la velocidad de transmisión del vapor de agua, la pérdida porcentual de humedad y el grosor. El parche con colofonia: Eudragit RL PM (6:4) dio como resultado una liberación de 2651 mcg en 24 horas. Con el objeto de mejorar la liberación, se incluyeron distintas proporciones de alcanfor en la formulación. El parche con colofonia: Eudragit RL PM (6:4) y un 5% p/v de alcanfor dio como resultado una liberación constante del fármaco a lo largo de un período de 24 horas. La formulación F8 resultó ser la más satisfactoria en lo que a las propiedades tecnológicas se refi ere. Se llevaron a cabo estudios posteriores de permeación e irritación de la piel en ratas y conejos respectivamente. Por lo tanto, se puede concluir que con el parche de colofonia: Eudragit RL PM en proporción 6:4 con un 5% p/v de alcanfor, se alcanzan los objetivos deseables en sistemas de administración transdérmica de fármacos tales como anular el efecto de primer paso, una amplia liberación y una frecuencia de administración reducida.A matrix dispersion type transdermal drug delivery system of Diltiazem Hydrochloride was developed using different ratios of rosin with Eudragit RL PM and polyvinyl pyrrolidone. The patch prepared by the combination of rosin and polyvinyl pyrrolidone was not transparent one, and shows an uneven distribution of polyvinyl pyrrolidone, which may be due to the hydrophilic nature of polyvinyl pyrrolidone. The effect of the polymers on the technological properties, i.e., drug release, water vapor transmission rate, percentage moisture loss and thickness were investigated. The patch containing rosin: Eudragit RL PM (6:4) showed a release of 2651 mcg in 24 h. In order to improve the release various proportions of camphor was included in the formulation. The patch containing rosin: Eudragit RL PM (6:4) with 5% w/v of camphor showed a sustained release of the drug extending over a period of 24 h. Formulation F8 emerged as the most satisfactory formulation as far as the technological properties were concerned. Further skin permeation and skin irritation studies were carried out on rat skin and rabbit respectively. Therefore it can be concluded that the patch containing rosin: Eudragit RL PM in the ratio 6:4 with 5%w/v of camphor achieved the desired objectives of transdermal drug delivery systems, such as overcoming of fi rst pass effect, extended release and reduced frequency of administration

Optimasi Produksi Hasil Perencanaan Sucker Rod Pump Terpasang Pada Sumur Tmt-y Di Tac-pertamina Ep Golwater Tmt

Sumur TMT-Y menggunakan sucker rod pump sebagai metode pengangkatan buatan dalam memproduksikan minyak. Data pada bulan Maret 2014 menunjukkan bahwa efisiensi volumetris sumur tersebut masih dibawah 70% sehingga perlu dilakukan peningkatan efisiensi volumetris diatas 70%. Peningkatan dilakukan dengan menggunakan cara trial and error terhadap parameter stroke length dan kecepatan pompa. Berdasarkan kemampuan berproduksi sumur, sumur TMT-Y belum mencapai produksi optimum sebesar 1195.58 bpd. Untuk menghasilkan produksi optimum sebesar 1195.58 bpd tersebut didapatkan nilai stroke length 192 inchi dan kecepatan pompa 12 spm