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Pocket formula for mass attenuation coefficient, effective atomic number, and electron density of human tissues 被引量:1
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作者 H.C.Manjunatha L.Seenappa 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第3期1-8,共8页
We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assign... We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assigned a new chemical formula for all studied tissues based on their composition. We have introduced a new parameter called effective composition index(C_(eff)). Based on this, we have introduced a new method to compute the effective atomic number. The evaluated photon interaction parameters are graphically represented. The evaluated average, maximum,minimum, and standard deviations of effective atomic number are tabulated. The proposed formula produces a mass attenuation coefficient, mass energy absorption coefficient, and effective atomic number from their 展开更多
关键词 Effective ATOMIC number mass ATTENUATION COEFFICIENT TISSUES
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Seasonal Variations of Number Size Distributions and Mass Concentrations of Atmospheric Particles in Beijing 被引量:3
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作者 于建华 Benjamin GUINOT +2 位作者 虞统 王欣 刘文清 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第3期401-407,共7页
Particle number and mass concentrations were measured in Beijing during the winter and summer periods in 2003, together with some other parameters including black carbon (BC) and meteorological conditions. Particle ma... Particle number and mass concentrations were measured in Beijing during the winter and summer periods in 2003, together with some other parameters including black carbon (BC) and meteorological conditions. Particle mass concentrations exhibited low seasonality, and the ratio of PM2.5/PM10 in winter was higher than that in summer. Particle number size distribution (PSD) was characterized by four modes and exhibited low seasonality. BC was well correlated with the number and mass concentrations of accumulation and coarse particles, indicating these size particles are related to anthropogenic activities. Particle mass and number concentrations (except ultra-fine and nucleation particles) followed well the trends of BC concentration for the majority of the day, indicating that most particles were associated with primary emissions. The diurnal number distributions of accumulation and coarse mode particles were characterized by two peaks. 展开更多
关键词 Beijing particles particle number size distribution mass concentrations black carbon ultra- fine particles
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Determination of Carbon and Nitrogen Isotope Fractions in Tartaric Acid, Oxalic Acid, Glucose and Fructose—National Center of High Technologies of Georgia
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作者 Lamzira Pharulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Bachana Sulava 《American Journal of Analytical Chemistry》 CAS 2024年第8期229-240,共12页
Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetabl... Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetables, and fruits. Understanding the isotopic compositions in organic compounds is crucial for comprehending various biochemical processes and the nature of substances present in different natural products. Tartaric acid, oxalic acid, glucose, and fructose are widely distributed compounds, including in vegetables and fruits. Tartaric acid plays a significant role in determining the quality and taste properties of wine, while oxalic acid is also prevalent but holds great interest for further research, especially in terms of carbon isotopic composition. We can unveil the mechanisms of processes that were previously impossible to study. Glucose and fructose are the most common monosaccharides in the hexose group, and both are found in fruits, with sweeter fruits containing higher amounts of these substances. In addition to fruits, wheat, barley, rye, onions, garlic, lentils, peppers, dried fruits, beans, broccoli, cabbage, tomatoes, and other foods are also rich sources of fructose and glucose. To determine the mass fraction of the carbon-13 isotope in these compounds, it is important to study their changes during natural synthesis. These compounds can be modified with a carbon center. According to the existing isotopic analysis method, these compounds are converted into carbon oxide or dioxide [1]. At this point, the average carbon content in the given compound is determined, but information about isotope-modified centers is lost. Dilution may occur through the transfer of other carbon-containing organic compounds in the sample or by dilution with natural carbon or carbon dioxide during the transfer process. This article discusses the possibility of carbon-13 isotope propagation directly in these compounds, both completely modified and modified with individual carbon centers. The literature provides information on determining carbon-13 substance in organic compounds, both with a general approach and for individual compounds [2] [3]. 展开更多
关键词 Tartaric Acid Oxalic Acid GLUCOSE FRUCTOSE mass Spectrum Ion Current Intensity mass Line mass number Molecular and Fragment Ions CARBON Carbon Center
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Influence of Anisotropic Permeability and Soret Effect on the Convective Heat and Mass Transfer through a Porous Cavity Saturated by a Non-Newtonian Fluid
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作者 Dieudonné Kouke Julien Yovogan 《Engineering(科研)》 2023年第12期843-866,共24页
In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq a... In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq approximations. The horizontal walls of the system are subject to vertical uniform fluxes of heat and mass, whereas the vertical walls are assumed to be adiabatic and impermeable. The Soret effect is taken into consideration. Based on parallel flow approximation theory, the problem is solved in the limit of a thin layer and documented the effects of the physical parameters describing this investigation. 展开更多
关键词 Soret number Heat and mass Transfer Non-Newtonian Fluid ISOTROPY Ani-sotropy Supercritical Rayleigh number
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Mass Constituents of a Flat Lattice Multiverse: Conclusion from Similarity between Two Universal Numbers, the Rocksalt-Type 2<i>D</i>Madelung Constant and the Golden Mean 被引量:2
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作者 Hans Hermann Otto 《Journal of Modern Physics》 2018年第1期1-13,共13页
In fairly good agreement with the consensus range of dark energy to matter this ratio of the critical density is suggested to be connected with the golden mean &phi;=0.6180339887, yielding for dark energy to matte... In fairly good agreement with the consensus range of dark energy to matter this ratio of the critical density is suggested to be connected with the golden mean &phi;=0.6180339887, yielding for dark energy to matter mass fractions .?Assuming the baryonic matter to be only 4.432%, the ratio of matter to baryonic matter would be , and further the ratio of dark matter to baryonic one . If one subtracts from the dark matter a contribution of antimatter with the same mass of baryonic matter, according to the antigravity theories of Villata respectively Hajdukovic, the remaining mass ratio would yield . Replacing the “Madelung” constant α of Villata’s “lattice universe” by &phi;, one reaches again 1 + &phi;as the ratio of the repulsive mass contribution to the attractive one. Assuming instead of a 3D lattice a flat 2D one of rocksalt type, the numerical similarity between the Madelung constant and φ&minus;1 could not be just coincidence. The proposed scaling of the cosmological mass fractions with the square of the most irrational universal number &phi;may indicate that the chaotic cosmological processes have reached a quite stable equilibrium. This may be confirmed by another, but similar representation of the mass constituents by the Archimedes’ constant &pi;, giving for respectively for the dark components . However, the intimate connection of φ with its reciprocal may ignite the discussion whether our universe is intertwined with another universe or even part of a multiverse with the dark constituents contributed from there. 展开更多
关键词 UNIVERSAL numberS Fractal numberS Golden Mean Archimedes’ CONSTANT Fibonacci numberS Madelung Constants Sommerfeld’s Fine Structure CONSTANT Euler number LATTICE UNIVERSE Reciprocal UNIVERSE Cosmological mass Fractions Hubble CONSTANT Gyromagnetic Factor
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铁尾矿混凝土力学性质及耐久性
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作者 龚新亚 刘颖 《矿产综合利用》 CAS 2024年第2期89-95,共7页
这是一篇陶瓷及复合材料领域的论文。为了研究铁尾矿混凝土在受硫酸钠溶液干湿循环作用后的力学特性和耐久性,开展了受硫酸钠溶液侵蚀混凝土的抗压实验、抗氯离子侵蚀实验、抗冻实验和水化特性实验,分析不同铁尾矿掺量、干湿循环次数、... 这是一篇陶瓷及复合材料领域的论文。为了研究铁尾矿混凝土在受硫酸钠溶液干湿循环作用后的力学特性和耐久性,开展了受硫酸钠溶液侵蚀混凝土的抗压实验、抗氯离子侵蚀实验、抗冻实验和水化特性实验,分析不同铁尾矿掺量、干湿循环次数、溶液浓度对混凝土力学性质和耐久性的影响。结果表明:在铁尾矿掺量为30%、干湿循环次数为60次和硫酸钠浓度为5%时,混凝土的质量损失率较小而抗压强度耐腐蚀系数较大。随着铁尾矿掺量的不断增大,混凝土的抗氯离子侵蚀性能、抗冻性能越好,水化反应放热量不断减小。 展开更多
关键词 陶瓷及复合材料 铁尾矿 干湿循环次数 质量损失率 抗氯离子侵蚀性能 水化反应
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绝经期压力性尿失禁合并膀胱过度活动综合征的危险因素研究
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作者 居锦芬 聂思佩 +2 位作者 李炜虹 吴艳 武茜 《临床误诊误治》 CAS 2024年第4期42-46,共5页
目的探讨绝经期压力性尿失禁(SUI)合并膀胱过度活动综合征(OAB)的危险因素。方法选取2019年10月—2022年10月收治的136例女性绝经期SUI为研究对象,依据膀胱过度活动综合征评分(OABSS)分为OAB(尿急评分≥2分,且总分≥3分)组25例和无OAB组... 目的探讨绝经期压力性尿失禁(SUI)合并膀胱过度活动综合征(OAB)的危险因素。方法选取2019年10月—2022年10月收治的136例女性绝经期SUI为研究对象,依据膀胱过度活动综合征评分(OABSS)分为OAB(尿急评分≥2分,且总分≥3分)组25例和无OAB组111例。比较2组相关临床资料、OABSS、焦虑自评量表(SAS)和抑郁自评量表(SDS)评分。采用单因素、多因素Logistic回归分析影响绝经期SUI患者合并OAB的相关因素。结果OAB组OABSS、SAS和SDS评分均高于无OAB组(P<0.01)。OAB组与无OAB组在体质量指数(BMI)、妊娠次数、盆腔手术史、合并糖尿病、便秘史、焦虑和憋尿习惯方面比较差异有统计学意义(P<0.05,P<0.01)。多因素Logistic回归分析显示,BMI>28 kg/m^(2)、妊娠次数≥2次、有盆腔手术史和有便秘史均为影响绝经期SUI合并OAB的独立危险因素(OR=2.208、2.307、2.651和2.686,P<0.05)。结论绝经期SUI患者合并OAB较为常见,临床需重点关注BMI>28 kg/m^(2)、妊娠次数≥2次、有盆腔手术史和有便秘史的患者。 展开更多
关键词 尿失禁 压力性 绝经期 膀胱过度活动综合征 危险因素 体质量指数 妊娠次数 便秘 焦虑
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新型管式搅拌反应器的气液传质特性
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作者 李天赐 赵秋月 +2 位作者 朱帅 郑明昭 张廷安 《中国有色冶金》 CAS 北大核心 2024年第1期105-111,共7页
多相体系的混合与传质性能直接影响多相反应过程,团队开发了从搅拌桨叶端出气的新型管式搅拌反应器。采用稳态亚硫酸盐法(FSM)研究反应器的气液传质性能,考察了通气流量Q、搅拌弗劳德数Fr和液含量ε对体积传质系数k_(L)a的影响。结果表... 多相体系的混合与传质性能直接影响多相反应过程,团队开发了从搅拌桨叶端出气的新型管式搅拌反应器。采用稳态亚硫酸盐法(FSM)研究反应器的气液传质性能,考察了通气流量Q、搅拌弗劳德数Fr和液含量ε对体积传质系数k_(L)a的影响。结果表明:增大Q和Fr可以有效提高k_(L)a;新型搅拌桨从桨叶端进气方式可以增强k_(L)a,相较传统反应器最大增强约2倍。反应器的气液传质性能在ε=0.5、Fr=0.054、Q=1.6 m^(3)·h^(-1)时最高,此时k_(L)a=0.032 4 s^(-1)。依据试验数据建立了关于k_(L)a的无量纲关联式,误差基本在25%以内,对后续反应器的改进和应用具有参考意义。 展开更多
关键词 多相反应器 曝气 弗劳德数 气液系统 气液传质 冶金设备
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Determination of Mass Transfer Parameters During Deep Fat Frying of Rice Crackers 被引量:2
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作者 Mohammad Taghi Hamed MOSAVIAN Vahid Mohammadpour KARIZAKI 《Rice science》 SCIE 2012年第1期64-69,共6页
The accuracy of the knowledge of mass transfer parameters (effective moisture diffusivity, mass transfer Biot number and mass transfer coefficient) in the case of frying food, is essential and important for designin... The accuracy of the knowledge of mass transfer parameters (effective moisture diffusivity, mass transfer Biot number and mass transfer coefficient) in the case of frying food, is essential and important for designing, modeling and process optimization. This study is undertaken to develop an approach for determining mass transfer parameters during frying of spherical rice cracker in sunflower oil at 150, 170 and 190 ℃. These parameters were evaluated from the plots of dimensionless concentration ratios against time of frying. Effective moisture diffusivity, mass transfer Biot number and mass transfer coefficient ranged between 1.24×10^-8 to 2.36×10^-8 m^2/s, 1.96 to 2.34 and 5.51×10^-6 to 9.70×10^-6 m/s, respectively. Effective moisture diffusivity and mass transfer coefficient were found to increase with an increasing frying temperature, whereas mass transfer Biot number decreased. An Arrhenius-type relationship was found between effective diffusivity coefficient and frying temperature. 展开更多
关键词 FRYING rice cracker effective moisture diffusivity mass transfer Biot number mass transfer coefficient
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GC-MS测定中间馏分油烃类分子组成研究与应用
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作者 王乃鑫 刘泽龙 +3 位作者 杨静 马苏甜 孙岩峰 刘颖荣 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第3期774-783,共10页
基于操作简便、普及度高的气相色谱-四极杆质谱(GC-MS),利用模拟碳数切割与碳数校正,建立快速分析中间馏分油烃类碳数分布分子组成表征方法。该方法与测定中间馏分油烃类族组成标准分析方法NB/SH/T 0606—2019使用相同的仪器配置,在不... 基于操作简便、普及度高的气相色谱-四极杆质谱(GC-MS),利用模拟碳数切割与碳数校正,建立快速分析中间馏分油烃类碳数分布分子组成表征方法。该方法与测定中间馏分油烃类族组成标准分析方法NB/SH/T 0606—2019使用相同的仪器配置,在不增加硬件设备与分析时间的条件下,30 min即可同时得到烃类族组成、碳数分布以及正、异构链烷烃碳数分布等分子组成信息。利用该方法测定的碳数分布数据与配置软电离源的气相色谱-场电离飞行时间质谱(GC-FI TOFMS)测定数据基本一致。利用烃类分子组成计算出的碳、氢元素含量与标准分析方法NB/SH/T 0656—2017的测定结果相符。根据GC-MS测定的烃类分子组成数据,预测了45个柴油的十六烷值,预测值与实测值的偏差在±2.0之间。建立的表征方法解决了以往只有使用配置软电离源的中高分辨率质谱才能实现中间馏分油烃类分子组成表征的难题,在保障数据质量的前提下,降低了仪器成本,节省了实验时间,提高了分析效率。 展开更多
关键词 气相色谱-质谱(GC-MS) 中间馏分油 碳数分布 烃类分子组成 十六烷值
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Black Carbon Instead of Particle Mass Concentration as an Indicator for the Traffic Related Particles in the Brussels Capital Region 被引量:1
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作者 Peter Vanderstraeten Michael Forton +1 位作者 Olivier Brasseur Zvi Y. Offer 《Journal of Environmental Protection》 2011年第5期525-532,共8页
The Brussels Capital Region has difficulties in meeting the stringent EU daily limit value for PM10 in all its measuring sites. Postponing the attainment of the deadline was not granted by the EU Commission, mainly du... The Brussels Capital Region has difficulties in meeting the stringent EU daily limit value for PM10 in all its measuring sites. Postponing the attainment of the deadline was not granted by the EU Commission, mainly due to insufficient judged measures to reduce road traffic emissions. However, a thorough analysis of the data makes clear that neither the particle mass concentration (PM10 and PM2.5) nor the particle number concentration are specific metrics for evaluating the particle pollution originated by traffic. In fact, increased formation of secondary aerosol, together with adverse meteorological conditions and the (re) suspension of the coarser fraction are by far the three main explanations for the numerous PM10 exceeding values. From our experience, amongst the particles measured, only the results for Black Carbon (BC), mainly present in the lower submicron range, are reflective of the direct influence of local traffic. Measured at two traffic sites along with PM mass and number concentrations, the data for Black Carbon show a striking correlation with nitrogen monoxide, a parameter strongly related with the proximity of the local traffic. The correlation factor between Black Carbon data and NO or NOX is much higher than between Black Carbon and the PM mass or number concentration. Therefore the assessment of traffic related particles should consider Black Carbon rather than PM10 or PM2.5. 展开更多
关键词 BLACK Carbon PM10 PM2.5 PARTICLE mass CONCENTRATION PARTICLE number CONCENTRATION
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Experimental mass transfer coefficients in a pilot plant multistage column extractor 被引量:3
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作者 Mehdi Asadollahzadeh Ahad Ghaemi +1 位作者 Meisam Torab-Mostaedi Shahrokh Shahhosseini 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第8期989-999,共11页
The volumetric overall mass transfer coefficients in a multistage column have been measured using axial dispersion model for toluene–acetone–water system. The effect of operating parameters on the volumetric overall... The volumetric overall mass transfer coefficients in a multistage column have been measured using axial dispersion model for toluene–acetone–water system. The effect of operating parameters on the volumetric overall mass transfer coefficients has been investigated for both mass transfer directions. The results show that the mass transfer performance is strongly dependent on rotor speed and mass transfer direction, although only slightly dependent on phase flow rates. In addition, empirical correlations to predict the overall mass transfer coefficients have been developed. The proposed correlations based on dimensionless numbers can be considered as a useful tool for the possible scale up of the multistage column extractor. 展开更多
关键词 MULTISTAGE COLUMN mass transfer COEFFICIENT AXIAL dispersion model SHERWOOD number
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Effects of thermophoresis particle deposition and of the thermal conductivity in a porous plate with dissipative heat and mass transfer
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作者 Joaquín Zueco O.Anwar Bég L.M.Lpez-Ochoa 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第3期389-398,共10页
Network simulation method(NSM) is used to solve the laminar heat and mass transfer of an electricallyconducting,heat generating/absorbing fluid past a perforated horizontal surface in the presence of viscous and Jou... Network simulation method(NSM) is used to solve the laminar heat and mass transfer of an electricallyconducting,heat generating/absorbing fluid past a perforated horizontal surface in the presence of viscous and Joule heating problem. The governing partial differential equations are non-dimensionalized and transformed into a system of nonlinear ordinary differential similarity equations,in a single independent variable,畏. The resulting coupled,nonlinear equations are solved under appropriate transformed boundary conditions. Computations are performed for a wide range of the governing flow parameters,viz Prandtl number,thermophoretic coeffcient(a function of Knudsen number),thermal conductivity parameter,wall transpiration parameter and Schmidt number. The numerical details are discussed with relevant applications. The present problem finds applications in optical fiber fabrication,aerosol filter precipitators,particle deposition on hydronautical blades,semiconductor wafer design,thermo-electronics and problems including nuclear reactor safety. 展开更多
关键词 Thermophoresis . MHD . Network simulation model . Heat and mass transfer- Hartmann number
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Bits, Mass and Acceleration Issues in BSC
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作者 Giuseppe Fazio Mauro Giaconi Angela D'Arienzo Davide Quatrini 《Journal of Physical Science and Application》 2014年第8期531-535,共5页
The goal of the present paper is to expand already published works in the frame of"Banded speed cosmology" (BSC). In particular this paper gives validated values for physical quantities not so far investigated in ... The goal of the present paper is to expand already published works in the frame of"Banded speed cosmology" (BSC). In particular this paper gives validated values for physical quantities not so far investigated in previous publications, i.e., the number of individual physical entity in the universe, as well as the maximum value for acceleration. Validates values mean identical quantities from a numerical point of view obtained with different theoretical procedures, additionally compared with data based on NASA observations with Planck probe. 展开更多
关键词 Banded speed cosmology minimum and maximum value for the mass number of mass unities maximum value for acceleration Bekenstein.
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Neutrino Properties Probed by Lepton Number Violating Processes
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作者 Sabin Stoica 《Open Journal of Microphysics》 2013年第3期5-9,共5页
Study of neutrino properties is nowadays one of the most active domains of research in physics. On the one hand, fundamental properties of the neutrinos like their absolute mass, their character (are they Dirac or Maj... Study of neutrino properties is nowadays one of the most active domains of research in physics. On the one hand, fundamental properties of the neutrinos like their absolute mass, their character (are they Dirac or Majorana particles?) and the number of neutrino flavors, are still unknown. On the other hand, the knowledge of these properties are of great importance since the neutrinos are very abundant in nature and play a key role in nuclear and particle physics, astrophysics and cosmology. In addition, the results of the neutrino oscillation experiments have convincingly showed that neutrinos have mass and mix, in contradiction to the initial assumptions of the Standard Model. In this context there is an increased interest in the study of the Lepton Number Violating (LNV) processes, since they are capable to decide on the above mentioned neutrino properties. Since recently, the neutrinoless double beta (0nββ) decay was considered the only process able to distinguish between Dirac or Majorana neutrinos and to give a hint on the absolute mass of the electron neutrino. At present, the increased luminosity of the LHC experiments at CERN makes it feasable the search for LNV processes at LHC as well. Besides the neutrino character, these studies can also shed light on the existence of other types of neutrinos (the sterile neutrinos), than the three known ones. In this paper, I make a brief review on our present knowledge about the neutrino properties and on the way they can be probed by LNV processes at low- and high-energies. Particularly, I refer to the 0nββ decay process and to the first attempts of searching of LNV processes in hadron collider experiments, particularly in LHC experiments at CERN-Geneva. 展开更多
关键词 NEUTRINOS NEUTRINO OSCILLATIONS Double Beta DECAY NEUTRINO mass LEPTON number VIOLATION
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Mass, Fine Structure Constant, and the Classification of Elementary Particles by Masses
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作者 Khachatur Kirakosyan 《Journal of Modern Physics》 2021年第7期988-1004,共17页
The equations of motion of physical bodies are given, the characteristic parameters of which become the basis for determining a fundamental property of all matter—“mass”. The equations of motion are characterized b... The equations of motion of physical bodies are given, the characteristic parameters of which become the basis for determining a fundamental property of all matter—“mass”. The equations of motion are characterized by two constants, the derivative of one of which is the fine structure constant. Using these constants, energy scales are compiled, which are the basis for classifying particles by mass. 展开更多
关键词 mass ENERGY STRUCTURE Quantum numbers Elementary Particles
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A proteomic approach to investigate the qualitative and quantitative polymorphism of <i>β</i>-lactoglobulin in ovine milk: Inference on gene copy-number variations
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作者 G. Picariello A. Di Luccia +3 位作者 P. Ferranti I. Alloggio F. Addeo E. Pieragostini 《Advances in Biological Chemistry》 2012年第3期207-217,共11页
The rationale of this work is based on recent evidences suggesting that: 1) both qualitative and quantitative β-lactoglobulin (β-LG) polymorphism may be found in bovine milk;2) quantitative polymorphisms are often t... The rationale of this work is based on recent evidences suggesting that: 1) both qualitative and quantitative β-lactoglobulin (β-LG) polymorphism may be found in bovine milk;2) quantitative polymorphisms are often the result of expression gradients in multiple copies of a gene;3) the β-LG gene is duplicated in the dog and bovine genome;4) mammary genes are highly conserved across Mammalia. Thus, an investigation was conducted on ovine β-LG polymorphism checking phenotypic evidence for copy-number variants of β-LG in sheep. To the purpose, 206 milk samples were collected, during a small-scale survey within sheep farms breeding Southern Italian breeds. PAGIF screening of the samples revealed that approximately 50% individuals exhibited β-LG polymorphism and 4 different quantitative patterns, which were characterized in detail by a proteomic approach relying on combined chromatographic and mass spectrometric techniques. The expected figures based on the expression gradient models were compared with well-established α-globin gene arrangements in sheep. The different phenotypes suggest the presence of both duplicate and triplicate BLG haplotypes. The occurrence of a triplicate haplotype was supported by population data. The current study supports the helpfulness of up-to-date proteomics for inferring copy number polymorphisms through the characterization of the phenotypic expression. 展开更多
关键词 QUANTITATIVE POLYMORPHISM β-Lactoglobulin HPLC-ESI MS MALDI-TOF mass Mapping GENE Duplication GENE Arrangements COPY-number Variations (CNVs)
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基于组合赋权的暴恐转向风险预测研究 被引量:1
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作者 赵晓翠 康昭 +2 位作者 田玲 惠孛 曾曦 《广西科学》 CAS 北大核心 2023年第1期89-99,共11页
研究群体性事件演变过程中的冲突升级引发暴恐转向的风险,对维护国家安全和社会稳定具有重要意义。本文提出基于词频-逆文档频率(Term Frequency-Inverse Document Frequency,TF-IDF)及三角模糊数(Triangular Fuzzy Number,TFN)的组合... 研究群体性事件演变过程中的冲突升级引发暴恐转向的风险,对维护国家安全和社会稳定具有重要意义。本文提出基于词频-逆文档频率(Term Frequency-Inverse Document Frequency,TF-IDF)及三角模糊数(Triangular Fuzzy Number,TFN)的组合赋权法,并融合贝叶斯网络(Bayesian Network,BN)构建风险转向预测模型。首先,通过分析促使事件态势演变的影响因素,建立暴恐转向指标体系,利用TF-IDF方法对社交媒体文本数据中的代表性高频词汇进行筛选和分类,计算对应指标的客观权重。其次,结合TFN和德尔菲法设计调查问卷,采用全积分值法对专家小组评判结果进行解模糊化处理,得到指标的主观权重。再次,根据博弈论组合赋权法得到综合权重,融合BN概率推理模型,预测发生暴恐转向的概率。最后,利用反向推理得出影响因素的后验概率,分析引发暴恐转向的主要因素,为相关部门采取针对性措施提供理论参考。实例结果显示暴恐转向风险的预测概率为81%,与实际事件态势发展情况相符,验证了本文模型对群体性事件态势发生暴恐转向风险具有可行、准确的预测。 展开更多
关键词 暴恐转向风险 群体性事件 三角模糊数 TF-IDF 贝叶斯网络
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高湿排风热质传递模型及不可逆换热过程分析
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作者 樊思雨 陈世强 +5 位作者 李瑾 黄敏华 吴世先 刘纯玉 吴涛 戚子特 《煤炭学报》 EI CAS CSCD 北大核心 2023年第6期2475-2483,共9页
如何高效提取矿井排风中蕴含的大量低品位能量,是工程领域内关键问题。针对喷淋式扩散塔热回收装置内,高湿排风与低温喷淋水的热质传递问题,构建并求解了基于传质单元数(NTU_(m))与刘易斯数(Le)的热质传递理论模型,开展了高湿排风与低... 如何高效提取矿井排风中蕴含的大量低品位能量,是工程领域内关键问题。针对喷淋式扩散塔热回收装置内,高湿排风与低温喷淋水的热质传递问题,构建并求解了基于传质单元数(NTU_(m))与刘易斯数(Le)的热质传递理论模型,开展了高湿排风与低温喷淋水直接接触式热质传递试验。运用火积耗散理论,明确了热质传递的实际不可逆换热过程,并揭示了Le与火积耗散热阻之间的相互关系。研究结果表明:高湿排风与低温喷淋水的热质传递过程具体表现为减湿冷却过程和类等湿冷却过程。NTU_(m)>0.1,高湿排风进行减湿冷却,经低温喷淋水换热后,最大温差可达到6.3℃,含湿量差为3.12 g/kg,该过程中Le偏离于1,Le与火积耗散热阻呈正比关系,当Le逼近于1,火积耗散热阻逼近于0,可达到最优换热效果;NTU_(m)<0.1,高湿排风进行类等湿冷却,主要表现为高湿排风经过减焓冷却达到饱和状态后,空气状态沿饱和线变化直至换热完成,且排风出口温度接近于排风进口露点温度。值得注意的是,类等湿冷却过程中热质传递火积耗散热阻远大于减湿冷却过程,高湿排风进行减湿冷却更有利于热质传递。在设计喷淋式扩散塔热回收装置时,为使换热单元内高湿空气进行减湿冷却,实现热湿能量的高效提取,风流速度应不大于4 m/s,水气比不低于0.2。 展开更多
关键词 高湿排风 热质传递 传质单元数 刘易斯数 火积耗散热阻
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昆山地区偏迟播小麦穗数与产量的相关性分析 被引量:1
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作者 张雅菁 史平 +1 位作者 孙柳青 吴建明 《耕作与栽培》 2023年第1期35-38,共4页
在偏迟播栽培条件下,对镇麦10号等3个品种,按穗数高、中、低3个类型在小局域地段进行随机取样,调查穗数、株高、产量、每穗粒数、千粒重等性状。结果表明,3个品种都表现穗型偏小、每穗粒数较少。穗数变化对每穗粒数、千粒重变化影响相... 在偏迟播栽培条件下,对镇麦10号等3个品种,按穗数高、中、低3个类型在小局域地段进行随机取样,调查穗数、株高、产量、每穗粒数、千粒重等性状。结果表明,3个品种都表现穗型偏小、每穗粒数较少。穗数变化对每穗粒数、千粒重变化影响相对较小。穗数与产量呈极显著正相关,在调查区间范围内,3个品种的穗数与产量符合直线回归关系。穗数与每穗粒数均呈负相关,中镇麦10号、镇麦15相关达极显著水平,扬麦16相关未达显著水平。穗数与株高呈正相关,3个品种都达极显著水平,其中扬麦16穗数达37.34万/667 m 2及以上时发生斜倒。根据结果本文提出了偏迟播小麦以足穗高产的栽培途径及必须重视的三项栽培措施。 展开更多
关键词 小麦 偏迟播 产量 穗数 千粒重 相关性
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