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Surface Modification of Polycarbonate Using Mesh Electrode at Atmospheric Pressure Discharge at 50 Hz
Get PDFThis paper reports the result of surface treatment of polycarbonate sample on atmospheric pressure dielectric barrier discharge (APDBD) in argon environment. The discharge was generated in parallel plate DBD system with a fine metal mesh below a barrier using a high voltage power supply (0-20KV) operating at line frequency, 50Hz. The main objective of the study is to investigate improvement of the hydrophilic property of the polymer after the treatment in plasma. The plasma treated samples were characterized by gravimetric method and contact angle measurement with two test liquids and the contact angle data were used for the calculation of surface energy of the samples with its polar and dispersive components. Our result showed that the discharge produces significant improvement in hydrophilicity just after 2 minutes of treatment reducing the contact angle from 88.28° to less than 55°. It was also found that the change in surface energy is mainly due to the increase in polar component of the surface energy
The Slow Focus Mode in Plasma Focus for Fast Plasma Stream Nano-Materials Fabrication: Selection of Energy of Bombarding Particles by Pressure Control
Get PDFAs a radiation source, the plasma focus (PF) operates in the time-matched regime (TMR). Maximum energy is pumped into the compression, resulting in large inductive voltages (Vmax), high temperatures, and copious multi-radiations. In this Fast Focus Mode (FFM), targets in front of the anode are subjected to strong bursts of fast ion beams (FIB), post-pinch fast plasma streams (FPS), followed by materials exploded off the anode by relativistic electron beams (REB). In INTI PF in hydrogen, as operational pressure (P) is increased beyond TMR, dynamics slow down, the minimum pinch radius ratio (kmin) increases, Vmax decreases, FIB reduces in energy per ion (U), in beam power (PFIB), and damage factor (DFIB), as operation moves from FFM into Slow Focus Mode (SFM). This pattern is the same for other gases, but for Ar, Kr, and Xe, radiative collapse becomes dominant, past the TMR. As P is increased further, there comes a point (slowest SFM or SSFM) where compression is so weak that the outgoing reflected shock barely reaches the incoming piston. At SSFM, kmin is maximum (typically > twice that at FFM), Vmax, PFIB, and DFIB are low, and we expect a significant reduction in anode boil-offs. However, FPS energy is near its highest. Operation near SSFM reduces FIB damage and anode sputters on-target, allowing the largest area of interaction, primarily with the FPS. The above is surmised from RADPF FIB code. Recent experiments in INTI PF confirm experimental observations (Rawat, private communication 2013) that such high-pressure operations produce a bigger area of more uniform interaction. This should improve the production of nano-materials, e.g., carbon nanotubes on graphite substrate. Operational pressure may be used to select FPS particle energy, enabling control of bombarding particle energy, in the range of tens to hundreds of eV, and thus contribute to making PF materials technology more of a science than the present state-of-the-art
Non-Compactness of a Closed and Bounded Set
Get PDFIf every closed and bounded set in a metric space is compact, the space is said to have the Heine-Borel property. This property holds in every finite dimensional normed space, but may not be true in general. Though its proof appears in many basic analysis courses, it is hard to motivate as the result is subtle and the applications are not obvious. Our goal is to provide an elegant proof as a resource for teachers that will enable them to motivate the study of this essential property and to understand the mathematics in it as a valuable teaching tool. 
An Overview on Gastroretentive Drug Delivery System
Get PDFOral controlled release and site-specific drug delivery systems have been of great interest in the pharmaceutical field to achieve improved therapeutic advantage. Drug absorption in the gastrointestinal tract is a highly variable procedure, and prolonging gastric retention of the dosage form extends the time for drug absorption. Gastroretentive drug delivery systems are one such novel approach to prolong gastric residence time, thereby targeting site-specific drug release in the stomach for local or systemic effects. This approach is useful particularly for drugs which have a narrow absorption window in the upper part of the gastrointestinal tract. Various approaches of gastroretentive drug delivery systems, such as floating and non-floating, have been discussed in this review. Additionally, this review provides an overview of the merits, demerits, and evaluation parameters of gastroretentive systems
Numerical Experiments to Obtain the Scaling Laws for Neutron Yield on Mather-Type Plasma Focus Machines Below 500 Joules
Get PDFIn this paper, we explain how we have fitted Lee‘s 5-phase and 6-phase model code to analyze the current waveforms of 6 small plasma focus machines (below 500 Joules) working in deuterium gas medium. Using the information from the code fitted to these current waveforms, the scaling laws for these small-energy machines were obtained as follows
Some Sequence Spaces and Their Matrix Transformations
Get PDFThe most general linear operator to transform from a new sequence space into another sequence space is actually given by an infinite matrix. In the present paper, we represent some sequence spaces and provide the characterization of (Sl∞ (p), l∞) and (Sl∞ (p), cs). 
Leaf Micromorphological Studies in Subfamily Bambusoideae and Pooideae from Gujarat, India
Get PDFLeaf is the most widely used vegetative organ for identification in plant taxonomy. Microscopic features such as epidermal cells, stomata, cuticle, surface contours, roughness and ornamentation are in use since the beginning of the last century. Information on foliar micromorphology can shed more light on structural features and their possible functional attributes. In the present study 14 species belongs 4 tribes has been studied from the vegetative characteristic features of the leaves. All the species has been studied for their variations at generic level and tried to utilize for preparation of artificial key. All the characters has been discussed at length and presented in a tabular form
A Study on Eco-Friendly Cost-Effective Earthbag House Construction
Get PDFThis report will highlight the benefits both in terms of CO2 reduction and cost-saving construction. This project will develop rigorous assessment methods and broaden applications. It is expected that the project will have an impact on construction practice and lead to more research in this area. The weakest specimens tested obtained maximum compressive strengths ranging from 120 kN/m to 140 kN/m, almost 10 times as great as those typically achieved by conventional stud-frame housing in terms of load per meter of wall length. The lowest load deformation response was observed for the G9 specimen group, at 0.7 kN/mm. The strongest and stiffest results were observed for the 3-bag soil-filled specimen, with load deformation responses ranging from 8 kN/mm to 15 kN/mm, and compressive strength two orders of magnitude higher than conventional stud-frame housing, ranging from 1100 kN/m to 1300 kN/m. Strength and stiffness values for medium soil-filled specimens measuring 508 mm x 914 mm were in the same range as the values for the small specimens. There was little difference in stiffness between specimens filled with topsoil and those filled with a 4:1 ratio of topsoil to masonry sand, though a small sample size prevents a meaningful statistical analysis of the variance between the two fill materials
Study of Leachate and Waste Composition at Different Landfill Sites of Nepal
No full textThe study focuses on waste composition and leachate characteristics at different landfill sites in Nepal, namely Sisdole (Kathmandu), Pokhara, and Karaute Dada (Dang). Waste composition was analyzed onsite, and leachate samples were collected for analysis. Results showed high organic content in waste at all sites, with percentages of 61.6%, 52.5%, and 65% at Sisdole, Pokhara, and Karaute Dada, respectively. The age of the landfill and waste composition significantly influenced leachate composition, with fresh leachate containing higher levels of BOD5 and CODcr. Landfills with a higher percentage of organic content exhibited elevated BOD5 and CODcr values
Coincidence and Common Fixed Point Theorem in Cone Metric
Get PDFThe aim of this paper is to establish a coincidence and common fixed point theorem for four self maps satisfying a contractive condition in a cone metric space. The intent of this paper is to introduce the concept of compatibility without assuming its normality