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A modular electromagnetic railgun accelerator facility named "RAFTAR" (i.e., Railgun Accelerator Facility for Technology and Research) has been commissioned and its performance has been characterized for high velocity impact testing on materials in a single-shot mode. In the first tests, RAFTAR demonstrated an acceleration of more than 1000 m/s for an 8 g solid aluminum-7075 armature projectile. The current fed was 220 kA, having a muzzle time of about 1.75 ms. It is a single pulse breech-fed rectangular bore (14 × 13 mm2) railgun, and its 1.15 m long barrel assembly consists of two parallel copper bars with an inter-gap of 13 mm that are encased within 50 mm thick high strength reinforced fiberglass sheets (Garolite G10-FR4) and bolted from both the sides. RAFTAR is powered by two capacitor bank modules that have a maximum stored energy of 160 kJ each (containing eight 178 μF/15 kV capacitors), two high power ignitron switches, and a pulse shaping inductor. To obtain consistent acceleration of the armature inside the barrel, reversal of driving current is prevented, and its pulse duration is stretched by tactical integration of the crowbar switch and bitter coil inductor in the circuit. Armature projectile velocity measurement in-bore and outside in free space was performed by the time-of-flight technique using indigenously made miniature B-dot sensors and a novel shorting-foil arrangement, respectively. The time resolved measurement of the in-bore armature evidenced a velocity-skin-effect in the high acceleration phase. There is good agreement between the experimentally measured and theoretically predicted efficiency, confirming the optimal choice of operating parameters. The conclusion summarizes important experimental findings and analyzes the underlying causes that limit the performance of railguns. [ABSTRACT FROM AUTHOR]

In flowering plants, the tapetum degeneration in post-meiotic anther occurs through developmental programmed cell death (dPCD), which is one of the most critical and sensitive steps for the proper development of male gametophytes and fertility. Yet the pathways of dPCD, its regulation, and its interaction with autophagy remain elusive. Here, we report that high-level expression of Arabidopsis autophagy-related gene BECLIN1 (BECN1 or AtATG6) in the tobacco tapetum prior to their dPCD resulted in developmental defects. BECN1 induces severe autophagy and multiple cytoplasm-to-vacuole pathways, which alters tapetal cell reactive oxygen species (ROS)-homeostasis that represses the tapetal dPCD. The transcriptome analysis reveals that BECN1- expression caused major changes in the pathway, resulting in altered cellular homeostasis in the tapetal cell. Moreover, BECN1-mediated autophagy reprograms the execution of tapetal PCD by altering the expression of the key developmental PCD marker genes: SCPL48 , CEP1 , DMP4 , BFN1 , MC9 , EXI1, and Bcl-2 member BAG5 , and BAG6. This study demonstrates that BECN1-mediated autophagy is inhibitory to the dPCD of the tapetum, but the severity of autophagy leads to autophagic death in the later stages. The delayed and altered mode of tapetal degeneration resulted in male sterility. • Arabidopsis BECN1 overexpression in post-meiotic tobacco tapetum affects its development. • BECN1 triggers severe autophagy and disrupts tapetal cell ROS homeostasis. • BECN1-induced autophagy reprograms the execution of tapetal PCD and inhibits it. • Transcriptome analysis showed altered gross cellular homeostasis in tapetal cells due to BECN1. • Delayed and altered mode of tapetal degeneration ultimately leads to male sterility. [ABSTRACT FROM AUTHOR]

• Autophagy is a conserved process regulating development and stress responses. • Genome-wide AuTophaGy-related genes (ATG) identified in 4 Gossypium species. • A total of 40 GhirATG, 33 GaATG, 34 GherbATG, and 25 GrATG genes were identified. • The ATG8 subclass genes were significantly expressed under stress conditions. • qRT-PCR of selected 12 GhirATGs in leaves treated with stress elicitors showed high expression. Autophagy is an evolutionarily conserved process mediated by AuTophaGy (ATG) genes, in which cellular components are degraded and recycled within vacuoles or lysosome. Yeast ATG was extensively studied; their homologs are reported in plants including Arabidopsis. However, they have not been reported in cotton. In the present study, the ATG cascade genes were studied in four Gossypium species, namely G. hirsutum, G. arboreum, G. herbaceum, and G. raimondii. A total of 40 GhirATG , 33 GaATG , 34 GherbATG , and 25 GrATG genes were identified in these species. These ATG sequences exhibited conserved ATG domains and other overlapping domains, including Ras, Pkinase, Snf7, WD40, Glyco_hydro_17, and bZIP_1, and were named based on their phylogenetic relationships with Arabidopsis ATGs. A phylogenetic analysis revealed evolutionary relationships among ATG genes among these species, as well as significant sub-clades indicating patterns of gene retention. Based on synonymous and non-synonymous substitutions, cotton groups diverged at different times from Arabidopsis. Gene structure analysis and chromosome localization showed exon-intron patterns and locations. Expression analysis of ATGs in different tissues during development and under stress conditions indicated their functional specificity. The ATG8 subclass genes were significantly expressed under abiotic stress conditions, indicating their role in stress response. In addition, qRT-PCR analysis of selected 12 GhirATGs in leaves treated with stress elicitors, MeJA, SA, NaCl, and PEG for varying time intervals showed a pattern of their significant upregulation. The findings contribute to our understanding of autophagy-related processes in cotton, including their potential role in stress response and development. [ABSTRACT FROM AUTHOR]

A reaction of fundamental and commercial importance is acetylene semi‐hydrogenation. Acetylene impurity in the ethylene feedstock used in the polyethylene industry poisons the Ziegler‐Natta catalyst which adversely affects the polymer quality. Pd based catalysts are most often employed for converting acetylene into the main reactant, ethylene, however, it often involves a tradeoff between the conversion and the selectivity and generally requires high temperatures. In this work, bimetallic Pd−Zn nanoparticles capped by hexadecylamine (HDA) have been synthesized by co‐digestive ripening of Pd and Zn nanoparticles and studied for semi‐hydrogenation of acetylene. The catalyst showed a high selectivity of ~85 % towards ethylene with a high ethylene productivity to the tune of ~4341 μmol g−1 min−1, at room temperature and atmospheric pressure. It also exhibited excellent stability with ethylene selectivity remaining greater than 85 % even after 70 h on stream. To the best of the authors' knowledge, this is the first report of room temperature acetylene semi‐hydrogenation, with the catalyst effecting high amount of acetylene conversion to ethylene retaining excellent selectivity and stability among all the reported catalysts thus far. DFT calculations show that the disordered Pd−Zn nanocatalyst prepared by a low temperature route exhibits a change in the d‐band center of Pd and Zn which in turn enhances the selectivity towards ethylene. TPD, XPS and a range of catalysis experiments provided in‐depth insights into the reaction mechanism, indicating the key role of particle size, surface area, Pd−Zn interactions, and the capping agent. [ABSTRACT FROM AUTHOR]

The results of characterization experiments carried out on a newly developed dense plasma focus device based intense pulsed neutron source with efficient and compact pulsed power system are reported. Its high current sealed pseudospark switch based low inductance capacitor bank with maximum stored energy of ~10 kJ is segregated into four modules of ~2.5 kJ each and it cumulatively delivers peak current in the range of 400 kA-600 kA (corresponding to charging voltage range of 14 kV-18 kV) in a quarter time period of ~2 μs. The neutron yield performance of this device has been optimized by discretely varying deuterium filling gas pressure in the range of 6 mbar-11 mbar at ~17 kV/550 kA discharge. At ~7 kJ/8.5 mbar operation, the average neutron yield has been measured to be in the order of ~4 × 109 neutrons/pulse which is the highest ever reported neutron yield from a plasma focus device with the same stored energy. The average forward to radial anisotropy in neutron yield is found to be ~2. The entire system is contained on a moveable trolley having dimensions 1.5 m × 1 m × 0.7 m and its operation and control (up to the distance of 25 m) are facilitated through optically isolated handheld remote console. The overall compactness of this system provides minimum proximity to small as well as large samples for irradiation. The major intended application objective of this high neutron yield dense plasma focus device development is to explore the feasibility of active neutron interrogation experiments by utilization of intense pulsed neutron sources. [ABSTRACT FROM AUTHOR]

The performance of railgap switch critically relies upon multichannel breakdown between the extended electrodes (rails) in order to ensure distributed current transfer along electrode length and to minimize the switch inductance. The initiation of several simultaneous arc channels along the switch length depends on the gap triggering technique and on the rate at which the electric field changes within the gap. This paper presents design, construction, and output characteristics of a coaxial cable based three-stage transmission line transformer (TLT) that is capable of initiating multichannel breakdown in a high voltage, low inductance railgap switch. In each stage three identical lengths of URM67 coaxial cables have been used in parallel and they have been wounded in separate cassettes to enhance the isolation of the output of transformer from the input. The cascaded output impedance of TLT is ~50 Ω. Along with multi-channel formation over the complete length of electrode rails, significant reduction in jitter (≤2 ns) and conduction delay (≤60 ns) has been observed by the realization of large amplitude (~80 kV), high dV/dt (~6 kV/ns) pulse produced by the indigenously developed TLT based trigger generator. The superior performance of TLT over conventional pulse transformer for railgap triggering application has been compared and demonstrated experimentally. [ABSTRACT FROM AUTHOR]

Characterization results of high-power microwave radiation, from an axial vircator driven by pulsed electron beam accelerator AMBICA-600 are reported in this paper. We present a study on variation in pulsed microwave power output and dominant frequency by discretely varying anode–cathode (A–C) gap. While keeping the cathode diameter fixed at 40 mm, for the A–C gap distance in the range 5–9 mm, dominant frequencies have been measured to be lying in the range 4.7–9.8 GHz. The trend of a subsequent increase in the dominant frequency at lower A–C gap distances (and vice versa) revealed that center frequency is mainly governed by the longitudinal size of the potential well. The highest microwave power of \sim14~MW for \sim75\-ns pulse duration was obtained at A–C gap of 7 mm having the dominant frequency in C-band at \sim6.9~GHz. The beam-to-microwave power conversion efficiency of \sim1.2\% has been demonstrated in our experiments. On the basis of power distribution pattern obtained by the gas breakdown technique, the dominant mode of emission is believed to be transverse magnetic mode. Relative analysis of frequency spectrums obtained for various A–C gap distances evidenced experimental recognition of optimum A–C spacing as a generation of narrowband distinct frequency peak of large magnitude with minimal mode hopping. [ABSTRACT FROM AUTHOR]

This paper reports the results of characterization and optimization experiments carried out on a newly developed NX-3 dense plasma focus device (20 kJ at 20 kV, a quarter time period of \sim\!\!3\ \mu\s, and 10 kJ/600 kA at 14 kV) at the Plasma Radiation Source Laboratory, NIE, Nanyang Technological University, Singapore. Initial experiments were conducted with an electrode assembly configuration having anode radius and length of 20 and 160 mm, respectively, for detailed neutron emission characterization of NX-3 device followed by further optimization of neutron yield using various other electrode configurations designed using the Lee Code. At \geq10-kJ operation, the average neutron yield on the order of 10^9 neutrons/pulse in 4\pi\sr was obtained for the deuterium filling gas pressure range of 6–8 mbar. The neutron yield of \sim\!\!4.6 \times 10^9 neutrons/pulse at 10 kJ/6 mbar is the highest ever reported for a device with the same stored energy. The neutron anisotropy measurements point to the beam–target mechanism as the dominant neutron production mechanism for NX-3 plasma focus device. Further optimization of neutron yield in NX-3 was achieved with the peak average neutron yield being enhanced from \sim\!\!(2.38 \pm 0.31) \times 10^9 neutrons/shot for the initial electrode configuration to about \sim\!\!(3.40 \pm 0.43) \times 10^9 neutrons/shot for the electrode configuration with anode radius and length of 26 and 140 mm, respectively. The analysis of neutron yield results for various electrode assembly configurations demonstrates the speed factor as a key optimization tool for maximization of neutron yield. [ABSTRACT FROM PUBLISHER]

A table top ~0.2-kJ miniature plasma focus (PF) device "FMPF-1" (2.4 µF, 27 ± 2 nH, T/4 ~400 ns, 9-14 kV) has been successfully used as a compact and portable, pulsed hard X-ray (HXR) source for fast (< 32-ns exposure time) radiography applications using Hydrogen (H2) as filling gas. The overall dimensions of the apparatus, which includes capacitor bank, sparkgap switch, and the focus chamber, are 0.2 m x 0.2 m x 0.5 m, and the system weighs about 25 kg. The time resolved information of HXR emission and their relative yield along the axial (0°) and radial (90°) directions are measured using a pair of cross-calibrated scintillator-photomultiplier detectors. The average pulse durations (full-width at half-maximum) of HXR pulse are measured to be 29±3 ns in axial direction and 18±2 ns in the radial direction. The average axial to radial HXR yield anisotropy is found to be 3.9 ± 0.9 at the optimum pressure of 3.5 mbar. The experimental estimation of the effective average energy of the HXR emission, with high-Z (Pb) insert in stainless steel anode is found to be in the range of 60-80 keV. The potential of the miniature PF as compact radiographic source is illustrated by radiographic imaging, with submillimeter range (< 0.3 mm) spatial resolution, of different objects placed outside the chamber. [ABSTRACT FROM AUTHOR]

Abstract: In this Letter we report the effect of two different cathode structures – tubular and squirrel cage, on neutron output from a miniature plasma focus device. The squirrel cage cathode is typical of most DPF sources, with an outer, tubular envelope that serves as a vacuum housing, but does not carry current. The tubular cathode carries the return current and also serves as the vacuum envelope, thereby minimizing the size of the DPF head. The maximum average neutron yield of for the tubular cathode at 4 mbar was enhanced to with squirrel cage cathode at 6 mbar operation. These results are explained on the basis of a current sheath loading/mass choking effect. The penalty for using a non-transparent cathode negates the advantage of the smaller size of the DPF head. [Copyright &y& Elsevier]

The increased interest in pulsed power field applications has generated the need for development of compact and remotely operated chargers driven by rechargeable batteries. With this objective, a compact and portable dc to dc Converter has been developed which has an output rating of 100 kV, 0.4 mA. The high voltage generation scheme uses a hybrid approach. The overall idea behind implementation of hybrid concept is to optimize voltage upliftment with suitable techniques for maximizing power delivered per unit volume. The proposed converter provides this feature and uses flyback converter in association with Cockcroft-Walton Multiplier [M. Jullian, Cockcroft-Walton Multiplier Optimum Design Guide V2.0, August 2005 (http//www.blazelabes.com)] for the generation of 100 kV dc from 12 V dc source, i.e., normal battery. In the first stage 12 V dc is modulated/chopped into series of high frequency pulses by pulse width modulator and then increased in level up to 16 kVpp by step up flyback transformer. Further by using n stage half wave series Cockcroft-Walton multiplier the voltage is stepped up to the level of 100 kV. As switching device, state of the art metal-oxide-semiconductor field-effect transistor has been used. The obtained voltage multiplier cascade efficiency is 82.64%, whereas overall power conversion efficiency of the charging power supply is 85.47%. The control unit has been fiber optically isolated from high voltage unit due to safety consideration. The presented article explores complete design and development approach of compact and portable 100 kV dc power supply which can be used for a variety of applications such as x-ray generation, ion implantation, charge particle acceleration, radio isotope production, etc. [ABSTRACT FROM AUTHOR]

Conventionally, Marx generators are used for the production of short duration, high voltage pulses but since many discharge gap switches are utilized for stepping up the voltage, there are many disadvantages. Here, an alternative and much simpler technique for the multiplication of nanosecond high voltage pulses has been presented in which multiplication takes place by switching single spark gap providing voltage gain of 'nxV'' where n is the subsequent number of stages. Stepped up high voltage pulse with fixed voltage gain of defined shape with fast rise time and good flat top is produced without using additional pulse-forming network. Its operation has been made repetitive by switching single spark gap. Multipurpose use, low cost, small size, light weight (weighing less than 50 kg) and portability are the additional benefits of the system. The reported nanosecond pulser has been made by cascading three stages of Blumlein. To cross check its performance the parasitic impedance of the system has been evaluated to realize its adverse effect on the voltage gain and pulse shape. Also its operation has been simulated by PSPICE circuit simulator program and good agreement has been obtained between simulated and experimental results. Applications of this pulse generator include X-ray generation, breakdown tests, ion implantation, streamer discharge studies and ultra wideband generation, among others. [ABSTRACT FROM AUTHOR]

Advancement of the gene expression study provides comprehensive information on pivotal genes at different cotton fiber development stages. For the betterment of cotton fiber yield and their quality, genetic improvement is a major target point for the cotton community. Therefore, various studies were carried out to understand the transcriptional machinery of fiber leading to the detailed integrative as well as innovative study. Through data mining and statistical approaches, we identified and validated the transcriptional biomarkers for staged specific differentiation of fiber. With the unique mapping read matrix of ~ 200 cotton transcriptome data and sequential statistical analysis, we identified several important genes that have a deciding and specific role in fiber cell commitment, initiation and elongation, or secondary cell wall synthesis stage. Based on the importance score and validation analysis, IQ domain 26, Aquaporin, Gibberellin regulated protein, methionine gamma lyase, alpha/beta hydrolases, and HAD-like superfamily have shown the specific and determining role for fiber developmental stages. These genes are represented as transcriptional biomarkers that provide a base for molecular characterization for cotton fiber development which will ultimately determine the high yield. [ABSTRACT FROM AUTHOR]

Purpose: To assess the real-world prevalence of microsatellite instability (MSI)/mismatch repair (MMR) testing and related tumor status in recurrent/advanced endometrial cancer patients in Europe. Methods: Data were from two multi-center, retrospective patient chart review studies conducted in the United Kingdom, Germany, Italy, France and Spain: The Endometrial Cancer Health Outcomes-Europe-First-Line (ECHO-EU-1L) study and the ECHO-EU-Second-Line (ECHO-EU-2L) study. ECHO-EU-1L included recurrent/advanced endometrial cancer patients who received first-line systemic therapy between 1/JUN/2016 and 31/MAR/2020 after recurrent/advanced diagnosis. ECHO-EU-2L included patients with recurrent/advanced endometrial cancer who progressed between 1/JUN/2016 and 30/JUN/2019 following prior first-line systemic therapy. Data collected included patient demographics, MSI/MMR tumor testing and results, and clinical/treatment characteristics. Results: ECHO-EU-1L included 242 first-line patients and ECHO-EU-2L included 475 s-line patients. For all patients, median age at recurrent/advanced diagnosis was 69 years, roughly half had endometrioid carcinoma histology and over 75% had Stage IIIB-IV disease at initial diagnosis. The prevalence of MSI/MMR testing in the first-line and second-line cohorts was similar (36.4 and 34.9%, respectively). Among those tested, a majority had non-MSI-high/MMR proficient tumors (80.7 and 74.7% among first- and second-line patients, respectively). About 15% had MSI-high/MMR deficient tumors in both cohorts, and a few patients had discordant results (3.4 and 10.8% among first- and second-line patients, respectively). Conclusion: Prior to the approvals of biomarker-directed therapies for recurrent/advanced endometrial cancer patients in Europe, there were low MSI/MMR testing rates for these patients of just over one-third. Given the availability of biomarker-directed therapies, increased MSI/MMR testing may help inform treatment decisions for recurrent/advanced endometrial cancer patients in Europe. [ABSTRACT FROM AUTHOR]

The present study is investigating the use of short carbon fiber (SCF) and silver‐coated hollow glass microsphere (Ag@HGM) reinforced epoxy light‐weight composites for electromagnetic interference (EMI) shielding applications in the X‐band frequency range (i.e., 8–12 GHz). The study found that Ag@HGM along with SCF significantly improved the dielectric properties of the composites and enhanced the EMI shielding effectiveness of 34.6 dB. Thermal analysis indicates that the sample shows a high rate of heat dissipation and good thermal conductivity. The dynamic mechanical analysis has indicated that the composite has improved storage modulus, glass transition temperature, and activation energy. Highlights: SCF and Ag@HGM epoxy composite is fabricated for EMI shielding application.Two steps: etching and electroless coating of HGM are used for silver coating.The addition of Ag@HGM has enhanced total SE from 27.4 to 34.6 dB.EM wave gets scattered, experiences internal reflections view SCF and Ag@HGM.Additionally, enhancement of thermal and mechanical properties is observed. [ABSTRACT FROM AUTHOR]

The effect of varied concentrations of deuterium-krypton (D2–Kr) admixture on the neutron emission of a fast miniature plasma focus device was investigated. It was found that a judicious concentration of Kr in D2 can significantly enhance the neutron yield. The maximum average neutron yield of (1±0.27)×104 n/shot for pure D2 filling at 3 mbars was enhanced to (3.14±0.4)×105 n/shot with D2+2% Kr admixture operation, which represents a >30-fold increase. More than an order of magnitude enhancement in the average neutron yield was observed over the broader operating range of 1–4 mbars for D2+2% Kr and D2+5% Kr admixtures. [ABSTRACT FROM AUTHOR]

In a 200 J fast miniature plasma focus device about 17- and 10-fold increase in x-ray yield in spectral ranges of 0.9–1.6 keV and 3.2–7.7 keV, respectively, have been obtained with deuterium-krypton (D2–Kr) admixture at operating pressures of ≤0.4 mbar. In the pressure range of >0.4–1.4 mbar, about twofold magnification in average x-ray yield along with broadening of optimum pressure range in both spectral ranges were obtained for D2–Kr admixtures. An order of magnitude enhancement in x-ray yields at low pressures for admixture operation will help in achieving high performance device efficiency for lithography and micromachining applications [ABSTRACT FROM AUTHOR]

We report the design and development of insulated gate bipolar junction transistor based high performance driver for operating thyratrons in grounded grid mode. With careful design, the driver meets the specification of trigger output pulse rise time less than 30 ns, jitter less than ±1 ns, and time delay less than 160 ns. It produces a -600 V pulse of 500 ns duration (full width at half maximum) at repetition rate ranging from 1 Hz to 1.14 kHz. The developed module also facilitates heating and biasing units along with protection circuitry in one complete package. [ABSTRACT FROM AUTHOR]

Dentoalveolar trauma occurs in relation to injuries of fall, road traffic accidents, sports injury or physical violence. There may be injury limited to the tooth, or may involve the periodontium around, or in severe cases, alveolar bone or oral mucosa may be traumatised. There can be myriad injuries of the same structure depending upon the severity of impact. The injuries of tooth most commonly being crown fractures, followed by root fractures, luxation or complete avulsion of the tooth. Every type of dentoalveolar injury requires a specific set of clinical protocols to be followed in order to successfully diagnose and manage the particular case. We hereby report a case of a 29-year-old male patient with a history of fall under the influence of alcohol, who had fallen flat on his face and had suffered intrusive luxation of permanent maxillary right central incisor and avulsion of permanent maxillary left central and lateral incisors. The exarticulated teeth still had slight soft tissue attachment to the socket. On the patients first visit to dental OPD, being a dental emergency, the avulsed teeth were immediately restored back into the socket under local anaesthesia after adequately irrigating and debriding the socket, followed by repositioning of the internally luxated tooth, so that all were in their correct anatomical position. After checking for occlusion, they were splinted in position with Erich’s arch bar and 26 gauge SS wire and after giving post-operative instructions patient was asked to follow up after 6 weeks. At 6 weeks, the affected teeth were found to be firm and so arch bar were removed. Patient was advised to follow up further. At periodic follow ups, the patient was asymptomatic and maintained adequate oral functioning of the injured teeth, thus with good patient compliance and proper diagnosis and treatment, dentoalveolar fractures can be managed successfully. The main purpose of this article is to lay emphasis on the timing of treatment of the dentoalveolar injuries. The earlier they are managed, the better is the outcome. [ABSTRACT FROM AUTHOR]

Studies of neutron emission from a dense plasma focus suggest that a significant fraction of neutron emission in some shots is caused by fast deuterons that have a prominent azimuthal component of motion. Recent examples are observations of long-lasting neutron emission in the side-on direction in PF-1000 and of neutron flux asymmetry (end/side) less than unity in Gemini. Such azimuthal motion of deuterons indicates the presence of an azimuthal electric field that accelerates them and a poloidal magnetic field that keeps them within the zone of acceleration. This in turn must be accompanied by poloidal magnetic flux emission (PMFE) from the plasma focus. Recently, a diagnostic technique for detection of PMFE has been proposed and demonstrated. This paper presents results of its successful replication and the first ever exploratory survey of PMFE emission using the UNU-ICTP plasma focus at the Nanyang Technological University, Singapore. [ABSTRACT FROM AUTHOR]

Titanium thin film was prepared on copper substrate by thermal evaporation method. Gettering property of titanium film for deuterium was studied for different values of temperature, pressure and time. The studies were carried out in an ultra high vacuum system. The substrate was mounted in the vacuum system on a heater whose temperature was controlled by PID controller. The titanium thin film was activated for 1 h at a temperature of 500 °C under vacuum. After activation, during cool down, the vacuum chamber was pressurized at various pressure values of deuterium and left for absorption for various time periods. Comparative studies of the amount of deuterium desorption for various charging pressure and exposure time were studied with the help of residual gas analyzer. Attempts were made to qualify the process of deuteration of the titanium film. The results of these studies are presented in this article. • Comparative study of deuteriated titanium thin film performed by RGA. • RGA spectrum reveals about surface limited and diffusion limited desorption. • Effect of charging pressure & duration on bulk concentration of deuterium studied. • Achievement of higher bulk concentration could be established through this study. [ABSTRACT FROM AUTHOR]

Abstract: An optical fiber, partially stripped of its cladding is shown to sense refractive index of a liquid in which the uncladded sensing region is immersed, to a high degree of precision and over a wide range of refractive index. The slope of sensor response is found to be non linear, can have either sign and can change sign at around refractive index of the fiber. The sensitivity of the sensor to refractive index change is dependent on cladding thickness and is a maximum at an intermediate thickness value. It is insensitive to the presence of absorption at the wavelength at which refractive index is being measured and to the chemical nature of the solute. Experiments designed to show that cladding modes are responsible for sensing are described. [Copyright &y& Elsevier]

Zirconium based alloys are proved to be a good material for hydrogen storage as well as a vacuum pump. A non evaporable getter pump based on St 172 was tested for deuterium storage capacity in a sealed off vacuum device. The vacuum in the range of ultra high vacuum was maintained by the getter pump by gettering. Initial vacuum was created by a turbo molecular pumping system. After activation of the getter, test chamber was charged at 1 bar and 3 bar deuterium pressure for 24 h in two different experimental campaigns. After charging with deuterium, the chamber was pumped to ultimate vacuum and isolated from the TMP. The partial pressure of deuterium for different temperature of the getter was measured in sealed condition. Higher charging pressure improves the partial pressure of deuterium during desorption cycle. The experimental details and the results are presented in this article. • St 172 NEG was tested for use as deuterium source in sealed off vacuum device. • Higher charging of deuterium is effective to get higher operational pressure. • Higher charging helps for low temperature operation for specific deuterium pressure. [ABSTRACT FROM AUTHOR]

A 200 kJ pulsed power system (PPS) has been built up to drive pulsed plasma devices. This PPS consists of two 100 kJ capacitor bank modules, each comprising of five capacitors of each 178~\mu \textF , a discharge switch, and a pulse-shaping unit. When both the banks are charged simultaneously to −15 kV using full charging technique, it delivers a peak current 100 kA at the load (damping resistor and pulse-shaping inductor). Later on, a plasma system will be attached at the load which will also have an inductive and resistive effect. A fiber-optic triggering unit controls both the modules and there exists a flexibility of sometimes operating a single module only, besides there are provisions for further up gradation of the PPS to a targeted 600 kJ. Prior to this development, PSpice simulation was carried out to estimate the parameters of the circuit components to achieve the required wave pulse with precision. Using these parameters, a design of the PPS was made keeping into account about the critical issues involved and the ratings of the components, some of which were fabricated in house. This paper basically includes the criticality surrounding the operation of a high-energy long-pulse PPS under negative operating voltage. [ABSTRACT FROM AUTHOR]

An investigation was carried out with bulk and pigeonpea rhizosphere soils collected from Middle Gangetic region of Uttar Pradesh (UP). Collected soils were analyzed for physicochemical characteristics, bacterial population and R/S ratio. In the present study, bacterial count of rhizosphere soils were found to range between 250x105 to 40x105 whereas in bulk soil ranging from 220x105 to 14x105. The R/S ratio ranging from 5.74 to 1.12, indicating positive rhizospheric effect in collected soil samples. In addition, bacterial population associated with bulk and pigeonpea rhizosphere soils were also evaluated in vitro plant growth promoting attributes. In the present investigation, 46%, 16.6%, 75% and 21% of bacterial population associated with rhizosphere soil were found to be phosphate solubilizing, IAA, siderophore and HCN producing respectively whereas in bulk soil 5.5%, 38.8% and 67% of bacterial population were found to be phosphate solubilizing, IAA and siderophore producing respectively. The results suggest that higher percentage of phosphate solubilizers, IAA, siderophore and HCN producers were found in rhizospheric soils of pigeonpea as comparison to bulk soils and may be exploited as biofertilizers or microbial inoculants in the soils of pigeon pea crops growing in the vicinity of middle Gangetic region of Uttar Pradesh. [ABSTRACT FROM AUTHOR]

Ferrocenylketene (1) is calculated to be destabilized by 1.6 kcal/mol relative to phenylketene (10) by B3LYP isodesmic comparison to the corresponding alkenes. Ketene 1 generated by Wolff rearrangement in CH3CN is identified by the IR band at 2119 cm-1 and has a rate constant for reaction with n-BuNH2 less than that for 10 by a factor of 5. 1,2-Bisferrocenyl-1,2-bisketene 18 and 1-ferrocenyl-2-trimethylsilyl-1,2-bisketene 21 were prepared by photochemical ring opening of the corresponding cyclobutenediones, and 18 undergoes rapid ring closure 67 times faster than the corresponding 1,2-diphenyl-1,2-bisketene, while bisketene 21 is longer lived than 18 by a factor of 3.2 ⊗ 104. [ABSTRACT FROM AUTHOR]

The experimental results of an air-core pulse transformer are presented, which is very compact (<10 Kg in weight) and is primed by a capacitor bank that is fabricated in such a way that the capacitor bank with its switch takes the shape of single-turn rectangular shaped primary of the transformer. A high voltage capacitor assembly (pulse-forming-line capacitor, PFL) of 5.1 nF is connected with the secondary of transformer. The transformer output voltage is 160 kV in its second peak appearing in less than 2 μS from the beginning of the capacitor discharge. The primary capacitor bank can be charged up to a maximum of 18 kV, with the voltage delivery of 360 kV in similar capacitive loads. [ABSTRACT FROM AUTHOR]