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Emission of high-energy alpha particles in nuclear reactions of ^(48)Ca and ^(56)Fe ions on ^(181)Ta and ^(238)U targets

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Chinese Physics C 2022年第11期46卷 177-194页

作者： Yu.E.Penionzhkevich V.V.Samarin S.m.Lukyanov V.A.maslov m.A.Naumenko Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear ResearchDubna 141980Russia Department of Experimental methods in Nuclear Physics National Research Nuclear UniversityMoscow 115409Russia Department of Nuclear Physics Dubna State UniversityDubna 141982Russia

The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are *** measurements were performed using the high-resolution magnetic analyzer mAVR with beams of ^(48)Ca(280 meV)and ^(56)Fe(320 and 400 meV)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation *** analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.

关键词： alpha particle energy spectra two-and three-body kinematic limits model of moving sources time-dependent Schrodinger equation

Vibrational characteristics of piping system in air conditioning outdoor unit

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Science China(Technological Sciences) 2011年第5期54卷 1154-1168页

作者： S. K. LOH W. F. FARIS m. HAmDI W. m. CHIN Department of Engineering Design & manufacture Faculty of Engineering University of Malaya Department of mechanical Engineering College of Engineering International Islamic University Malaysia O.Y.L. R&D Sdn Bhd Sungai Buloh Selangor Darul Ehsan Malaysia

The modal analysis of piping system in air conditioner (AC) outdoor unit is essential to investigate the vibration properties of the system. In view of the growing significance of numerical finite element (FE) model for vibration behaviour prediction, the AC piping elastic end support characterization has been explored. The axial and radial stiffness variables (ka, kr1, kr2) of the compressor-piping mounting are obtained and represented by dynamic stiffness of compressor grommet. They are obtained from dynamic load deflection test based on compressor operating condition such as excitation frequency and amplitude. The unknown stiffness variables of the other tube end (chassis-piping mounting) are determined by parameter fine tuning. An experimental modal analysis using impact hammer test has also been employed to determine the vibration properties such as natural frequencies, mode shapes and damping ratio of the piping structures. The modal parameters acquisition using SCADAS mobile acquisition system and LmS Impact Testing software is compared with the corresponding simulated modal properties using Abaqus. most of the simulated natural frequencies achieve good correlation with the measured frequencies and it is reasonably a good prediction model to predict vibration behaviour of AC piping structures.

关键词： air conditioning outdoor unit piping modal analysis vibration characteristics

Efficient Resource Allocation in Fog Computing Using QTCS model

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Computers, materials & Continua 2022年第2期70卷 2225-2239页

作者： m.Iyapparaja Naif Khalaf Alshammari m.Sathish Kumar S.Siva Rama Krishnan Chiranji Lal Chowdhary School of Information Technology and Engineering Vellore Institute of TechnologyVellore632014India mechanical Engineering University of HailSaudi Arabia

Infrastructure of fog is a complex system due to the large number of heterogeneous resources that need to be *** embedded devices deployed with the Internet of Things(IoT)technology have increased since the past few years,and these devices generate huge amount of *** devices in IoT can be remotely connected and might be placed in different locations which add to the network *** time applications require high bandwidth with reduced latency to ensure Quality of Service(QoS).To achieve this,fog computing plays a vital role in processing the request locally with the nearest available resources by reduced *** of themajor issues to focus on in a fog service is managing and allocating *** theory is one of the most popular mechanisms for task *** this work,an efficient model is designed to improve QoS with the efficacy of resource allocation based on a Queuing Theory based Cuckoo Search(QTCS)model which will optimize the overall resource management process.

关键词： Queuing theory Cuckoo search QoS resource allocation energy efficiency

Introduction of Damping,Synchronizing and Inertial Effects Using Controlled Power Injection Devices

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CSEE Journal of Power and Energy Systems 2017年第4期3卷 408-418页

作者： Kaustav Dey P.Agnihotri A.m.Gole A.m.Kulkarni Department of Electrical Engineering Indian Institute of TechnologyBombayIndia Department of Electrical and Computer Engineering University of ManitobaCanada

This paper presents a theoretical study of damping,synchronizing and inertial control laws,implemented using controllable power injection devices like HVDC,FACTS or renewable-energy/storage systems which have power-electronic grid *** approach is to use a simplified dynamical model of a power system to arrive at generalized results regarding the effect of the strategies on the electro-mechanical dynamics of the *** results are not dependent on the size,network topology and operating condition of the power *** paper presents a differential-algebraic formulation and generalized eigenvalue analysis to facilitate a unified study of the effects of the control laws on the electro-mechanical *** damping,synchronizing and inertial control laws can themselves be extended to include the possibility of mutualdamping,synchronizing and inertial effects when multiple devices are *** control laws are not only simple and intuitive,but also are found to have a predictable and generally beneficial impact on the electro-mechanical dynamics of the grid,even when detailed models are considered.

关键词： Dynamic stability high voltage direct current(HVDC) inertia emulation power system control

ImPROVEmENT OF TYPE IV CRACKING RESISTANCE OF 9Cr HEAT RESISTING STEEL WELDmENT BY BORON ADDITION

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Acta metallurgica Sinica(English Letters) 2004年第4期17卷 331-337页

作者： m.Tabuchi m.Kondo T.Watanabe H.Hongo F.Yin F.Abe National Institute for materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 Japan

Creep lives of high Cr ferritic heat resisting steel weldments decrease due to Type Ⅳ fracture, which occurs as a result of formation and growth of creep voids and cracks on grain boundaries in fine-grained heat affected zone (HAZ). Because boron is considered to suppress the coarsening of grain boundary precipitates and growth of creep voids, we have investigated the effect of boron addition on the creep properties of 9Cr steel weldments. Four kinds of 9Cr3WSCoVNb steels with boron content varying from 4.7×10-5 to 1.8×10-4 and with nitrogen as low as 2.0×10-5 were prepared. The steel plates were welded by gas tungsten arc welding and crept at 923K. It was found that the microstructures of HAZ were quite different from those of conventional high Cr steels such as P91 and P92, namely the fine-grained HAZ did not exist in the present steel weldments. Boron addition also has the effect to suppress coarsening of grain boundary carbides in HAZ during creep. As a result of these phenomena, the welded joints of present steels showed no Type Ⅳ fractures and much better creep lives than those of conventional steels.

关键词： high Cr heat resistant steel welded joint boron addition Type IV fracture

Determinants of the Specif icity of Protein Targeting to Chloroplasts or mitochondria

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molecular Plant 2019年第7期12卷 893-895页

作者： Lucas mcKinnon Steven m.Theg Department of Plant Biology University of California Davis Davis CA USA

Chloroplasts and mitochondria are both thought to have arisen through primary endosymbiosis (Kutschera and Niklas, 2005). As each organelle evolved, most of its genome was transferred to the host nucleus resulting in the vast majority of its proteome being nuclear encoded and synthesized on cytosolic ribosomes (Shi and Theg, 2013).

关键词： Chloroplasts mitochondria

Thiopurine use associated with reduced B and natural killer cells in inflammatory bowel disease

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World Journal of Gastroenterology 2017年第18期23卷 3240-3251页

作者： James D Lord Donna m Shows Translational Research Program Benaroya Research Institute Gastroenterology Division Virginia Mason Medical Center

To identify which blood and mucosal lymphocyte populations are specifically depleted by thiopurine use in *** thiopurines azathioprine and 6-mercaptopurine have been a mainstay of inflammatory bowel disease (IBD) therapy for decades, but their mechanism of action in vivo remains obscure. Although thiopurines are lymphotoxic at high doses, and have been reported to cause T cell apoptosis in vitro, their ability to control IBD at lower doses suggests that they may selectively deplete particular lymphocyte populations. Blood cells from 19 IBD patients on a thiopurine, 19 IBD patients not on a thiopurine, and 38 matched healthy control subjects were analyzed by multiple multi-color flow cytometry panels to quantify the immune cell subsets contained therein, both as a percent of cells, and as an absolute cell count. Similar analyses were performed on colon biopsies from 17 IBD patients on a thiopurine, 17 IBD patients not on a thiopurine, and 49 healthy screening colonoscopy *** blood counts revealed lower lymphocyte, but not monocyte or granulocyte, counts in IBD patients who were taking thiopurines at the time of sampling. This reduction was restricted to CD3-negative lymphocytes, wherein both natural killer (NK) and B cells were significantly reduced among thiopurine recipients. Among CD19+ B cells, the transitional B cells were particularly depleted, being nearly absent in both blood and colon biopsies of thiopurine recipients. No differences were associated with thiopurine use in CD8+ T cells, mucosa-associated invariant T (mAIT) cells, invariant natural killer T (iNKT) cells, gamma/delta T cells, Th1, Th17, regulatory T cells (Tregs) or naïve CD4+ T cells. However, patients with IBD had significantly more circulating FOXP3+, Helios+ Tregs and fewer iNKT and mAIT cells than healthy *** use is associated with reduced B and NK cell, but not T cell, subpopulations in the blood of IBD patients.

关键词： Thiopurine Azathioprine mercaptopurine Lymphocyte Natural killer cell Transitional B cell Inflammatory bowel disease

Non-equilibrium carrier capture,recombination and annealing in thick insulators and their impact on radiation hardness

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Journal of Semiconductors 2016年第11期37卷 73-79页

作者： G.I.Zebrevt m.G.Drosdetsky A.m.Galimov The Department of micro-and Nanoelectronics of National Research Nuclear University"mEPHI" Moscow 115409Russia

This paper describes an approach to prediction of the thick insulators＇ radiation response based on modeling of the charge yield, which is dependent on irradiation temperature, dose rate, and electric field magnitudes. Temperature behavior of the charge yield and degradation saturation due to the interface precursor depletion has been modeled and simulated. Competition between the time-dependent and true dose rate （ELDRS） effects has been simulated and discussed within a framework of the rate-equation-based mathematical model. It was shown that the precursor trap in the thick insulating oxides can be important at high dose rates. It was also shown that full filling of the shallow hole traps in the insulating oxide bulk can cause suppression of dose-rate sensitivity at relatively high dose rates, especially in thick insulators.

关键词： bipolar devices total dose effects dose rate effects ELDRS insulators modeling

Optimization of enzymatic hydrolysis of cassava to obtain fermentable sugars

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第7期13卷 579-586页

作者： Renata m.COLLARES Luiza V.S.mIKLASEVICIUS mariana m.BASSACO Nina P.G.SALAU marcio A.mAZUTTI Dilson A.BISOGNIN Lisiane m.TERRA Department of Chemical Engineering Federal University of Santa MariaAv.Roraima 1000Santa Maria 97105-900Brazil Department of Horticulture Federal University of Santa MariaAv.Roraima 1000Santa Maria 97105-900Brazil

This work evaluates the enzymatic hydrolysis of starch from cassava using pectinase,α-amylase,and amyloglucosidase.A central composite rotational design(CCRD)was carried out to evaluate the effects of amyloglucosidase,pectinase,reaction time,and solid to liquid *** the experiments were carried out in a bioreactor with working volume of 2 *** 98%efficiency hydrolysis was obtained,resulting in a concentration of total reducing sugar released of 160 g/*** was concluded that pectinase improved the hydrolysis of starch from *** time was found to be significant until 7 h of reaction.A solid to liquid ratio of 1.0 was considered suitable for hydrolysis of starch from *** was a significant variable in the process:after its addition to the reaction media,a 30%-50%increase in the amount of total reducing sugar released was *** optimal conditions the maximum productivity obtained was 22.9 g/(L.h).

关键词： Cassava Enzymatic hydrolysis Enzyme reactor Starch