高功率激光二极管抽运的镱钠共掺氟化钙连续激光器

掺镱氟化钙(Yb3+:CaF2)激光器是最近国际上研究的热点之一,2008年报道的该类激光器,在64 W激光二极管(LD)的抽运下,实现了平均输出功率10.2 W的连续激光输出.利用国产镱钠共掺的氟化钙(Yb,Na:CaF2)激光晶体,采用三镜折叠腔型和激光二极管抽运,获得了该类激光器(Yb,Na:CaF2/Yb:CaF2)的高功率连续输出.实验参数为:输出耦合镜的透过率为4%,激光二极管的最大输出功率为40 W,中心波长为976 nm.当吸收抽运功率18.2 W时,获得了14.5 W的最高功率连续激光输出,相应的斜率效率为80%.结果表明,国产Yb,Na:CaF2晶体具有低激光阈值和高负载能力,是一种优良的高功率激光材料.     

重质塔河原油的减粘裂化工艺

塔河原油是一种劣质、重质原油,该原油通过减粘裂化装置加工可得半成品的轻油,还可以得到合格的燃料油。     

A METHOD FOR CALCULATING THE EXTENT OF REACTION OF SOLID PARTICLES WITH FLUID IN COMPLETELY MIXED REACTORS CONNECTED IN SERIES

When solid particles react with a fluid,the overall rate is influened by the fraction of the solidunconverted as well as by the operating conditions such as temperature and pressure.Calculation of solidsconversion in the individual reactor of a multi-stage reactor system has therefore to be based upon thesolids residence time distribution (RTD) in the respective stages.By using either the Dirac function δ(0) or the probability density function of the sum of independentrandom variables,the solids RTD in any stage of completely mixed reactors connected in series with nointerstage backflow has been obtained.The latter method has also been used in deriving general formu-las for the calculation of solids conversion when the order of chemical reaction is simple.For complexchemical reaction rate equations a stagewise procedure for numerical computation is proposed,and twocases are discussed according to whether the rate equation is expressed in its integral or differential formrespectively.     

Mutations in calpastatin and μ-calpain are associated with meat tenderness,flavor and juiciness in Hanwoo (Korean cattle): Molecular modeling of the effects of substitutions in the calpastatin/μ-calpain complex

The objective of this study was to evaluate the effects of seven single nucleotide polymorphisms (SNPs) in Calpain 1 and Calpastatin genes previously associated with meat tenderness attributes in other cattle breeds in Korean Hanwoo cattle. The Hanwoo resource population was used to study association of 7 SNPs with beef tenderness, flavor, juiciness, intramuscular fat and shear force. In this association study, CAST:c.182A > G (+ 0.14, P = 0.04) and CAST:c.1985G > C (− 0.12, P = 0.02) had significant effects on juiciness, but no effects on other traits. In contrast, CAPN1:c.1589G > A was associated with meat tenderness (P = 0.01) and juiciness (P = 0.04). The CAPN1:c.1589G > A (Val530Ile) SNP marker displayed significant effect on the meat tenderness score which is strongly supported by molecular modeling of the CAPN1:c.1589G > A (Val530Ile) variant that inhibits CAST protein from binding more strongly than the wild-type protein, which may explain its effect on meat tenderness.     

Aluminum based reflective nanolens arrays to improve the effectiveness of ultraviolet inactivation of Escherichia coli O157:H7 and Listeria monocytogenes in water and a sucrose solution

Food Science and Biotechnology - Aluminum based reflective nanolens arrays were developed via a series of aluminum electropolishing and anodization steps with subsequent selective dissolution of...     

微冻对南美白对虾质构的影响

以南美白对虾为对象,研究了其在-3℃微冻条件下质构参数(硬度、弹性、剪切力,咀嚼性、黏附性、胶黏性)的变化,同时考察了TVBN值、汁液流失率和感官特性的变化。结果表明:随着贮藏时间的延长,TVBN和汁液流失率均呈上升趋势;在贮藏至第14天以前,硬度、弹性、剪切力、咀嚼性呈上升趋势,之后逐渐下降,而黏附性一直呈现上升趋势,胶黏性呈下降趋势;结合TVBN值、汁液流失率和感官特性测定结果,南美白对虾质构测定结果能够较客观的表现其品质。     

小杂粮市场竞争力分析及产业开发研究

小杂粮营养丰富，医食同源，极具产业化开发潜力。通过对小杂粮的生产成本和效益、品质优势、价格优势及市场前景等方面的研究和分析，表明其具有较强的市场竞争力。种植分散、生产水平低；商品质量差；加工工艺落后，出口市场狭窄；产业化体系不健全是小杂粮产业开发的主要制约因素，并据此提出建设优质小杂粮生产基地、实施品牌战略、改进加工工艺、健全小杂粮市场营销体系，拓宽市场等对策措施。     

Overview of pharmacological activities of Andrographis paniculata and its major compound andrographolide

Abstract

Andrographis paniculata (A. paniculata) is a medicinal plant traditionally used as anti-inflammation and anti-bacteria herb. Andrographolide, the major active component of A. paniculata, exhibits diverse pharmacological activities, including anti-inflammation, anti-cancer, anti-obesity, anti-diabetes, and other activities. In this article, we comprehensively review the therapeutic potential of A. paniculata and andrographolide focusing on the mechanisms of action and clinical application. We systemically discuss the structure-activity relationship of andrographolide and derivatives. Despite the various pharmacological activities and formula of A. paniculata and andrographolide, we propose further development of more structural derivatives of andrographolide with reduced toxicity and increased therapeutic efficacy is still needed for the clinical application of this ancient mighty herb and its major component.     

动力学模型在鱼肉品质变化中的应用

考察了不同温度下鱼肉贮藏过程中细菌总数、挥发性盐基氮值随存放时间的变化规律及其动力学特性;建立了细菌总数、挥发性盐基氮值与贮藏温度和时间的动力学模型。贮藏过程中鱼肉的细菌总数、挥发性盐基氮值随贮藏时间的延长而增加,随贮藏温度的增加而上升。细菌总数和挥发性盐基氮值对一级化学反应模型和Arrhenius方程具有较高的拟合精度。