Experimental Investigation on Promoting Effect of Composite Promoting Agents on Natural Gas Hydrate Formation

An experiment on effects of composite promoting agents composed of surfactants and liquid hydrocarbons on hydrate formation was conducted and the hydrate formation temperature,pressure,induction time and rate in the presence of different composite promoting agent packages were measured.The surfactants used covered sodium dodecyl sulfate(SDS),sodium dodecyl benzene sulfonate(SDBS) and 2-octyl sodium dodecyl sulfate(GC20S),and the liquid hydrocarbon additives utilized included cyclopentane(CP) and methyl cyclohexane(MCH).It appeared that all these combinations of composite promoting agents could promote hydrate formation.The type II hydrate formation conditions using composite promoting agents composed of CP and GC20S were the mildest and the induction time was the shortest;whereas the type H hydrates formation conditions using composite promoting agents composed of MCH and GC20S were the mildest and the induction time was also the shortest.

Natural compounds as anticancer agents: Experimental evidence

Cancer prevention research has drawn much attention worldwide. It is believed that some types of cancer can be prevented by following a healthy life style. Cancer chemoprevention by either natural or synthetic agents is a promising route towards lowering cancer incidence.In recent years, the concept of cancer chemoprevention has evolved greatly. Experimental studies in anima models demonstrate that the reversal or suppression of premalignant lesions by chemopreventive agents is achievable. Natural occurring agents such as dietary phytochemicals, tea polyphenols and resveratrol show chemopreventive activity in animal models. Moreover,clinical trials for testing the safety and efficacy of a variety of natural agents in preventing or treating human malignancy have been ongoing. Here, we summarize experimental data on the chemopreventive or tumor suppressive effects of several natural compounds including curcumin,(-)-epigallocatechin-3-gallate, resveratrol, indole-3-carbinol, and vitamin D.

Understanding the Effect of Zinc Oxide(ZnO)With Carbon Black Coupling Agent on Physico-Mechanical Properties in Natural Rubber Matrix

Natural rubber(NR)is not only the main compounding ingredient used to make the majority of components of tires as well as other rubber products,as it plays a significant role in ensuring that they operate well and complies with environmental standards.The applications of NR products are lim-ited to high temperatures due to the revision tendency of NR vulcanizate.To address these issues,the potential engagement of a carbon black(CB)coupling agent(CA)in the presence of metal oxide i.e.Zinc Oxide(ZnO)was investigated in an NR-based system.This CA has dual functionality on physicomechanical properties.CA has the ability to reduce hysteresis loss as well as improve anti-reversion properties and these properties thorough-ly depend on the presence of ZnO.While ZnO was added to the master formulation,a 65%improvement in reversion properties was observed.On the other hand,while ZnO fully transferred to the final formulation,bound rubber(BR)content increased by 19%,the difference in storage modulus(ΔG’)is reduced by 22%,cure rate index(CRI)improved by 14%,loss tangent(tanδ)reduced by 18%and slightly improve in elongation at break compared to control compound.Thermo-gravimetric analysis(TGA)was engaged to understand the thermal stability and degree of purity of CA.A differential Scanning Calorimeter(DSC)was used to detect the phase tran-sition of CA.Fourier Transform Infrared Spectrum(FTIR)was adopted to detect the presence of carboxyl and amine groups in the CA moiety.Payne effect,BR content and Transmission Electron Microscope(TEM)were em-ployed to investigate the micro-level dispersion of CB in the natural rubber(NR)matrix.

Antioxidant Properties of Rosemary and Its Potential Uses as Natural Antioxidant in Dairy Products—A Review

Dairy products contain lipids rich in polyunsaturated fatty acids and their esters are easily oxidized by molecular oxygen over time. Deleterious changes in dairy products caused by lipid oxidation include not only loss of flavour or development of off-flavours, but also loss of colour, nutrient value, and the accumulation of compounds, which may be detrimental to the health of consumers. One of the most effective ways of retarding lipid oxidation in dairy products is to incorporate antioxidants. Sometimes synthetic phenolic antioxidant, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are used to delay this oxidation. Supplementation dairy products with natural antioxidants (polyphenolic compounds) are better using than synthetic antioxidant and could be potentially. The use of rosemary as natural antioxidant in dairy products can reduce the rate of lipid oxidation and hydrolysis besides may be beneficial in increasing the shelf life of these products. This supplementation will move these products into the functional food area under new category as healthy dairy products. This literature review covers the research that has focused on rosemary as antioxidant and anti-inflammatory agent that can inhibit the lipid oxidation and have health benefits by preventing carcinogens from binding to DNA, fight and stop pain. In this review, we survey the previous studies that were conducted on the application of rosemary extract as an antioxidant to extend the shelf life and to minimize nutritional losses of dairy product.

Recent advances in the managements of type 2 diabetes mellitus and natural hypoglycemic substances

Diabetes has become a global concern at present,among which type 2 diabetes mellitus(T2DM)accounts for approximately 90%-95%of patients.T2DM is a type of metabolic disorder syndrome that results from a genetic defect,and it is based on insulin resistance and an insulin secretion disorder.The occurrence of T2DM is usually the outcome of both genetic and environmental factors and their interactions.The etiology and pathogenesis of diabetes have not been fully elucidated,and no radical therapeutic cure has been found.Patients with T2DM suffer from complications such as the development of a chronic hyperglycemic condition and even serious metabolic disorders and organ damage in the body and depression and dementia,in addition to other chronic complications.Many studies have suggested that diet is crucial in the development of diabetes and the control of blood glucose.Natural substances have the characteristics of low toxicity and few side effects and may be key to the development of diabetic health products and preventive treatments.This paper reviews the etiology,pathogenesis,risks,treatments and diets related to T2DM to summarize the types of recently available natural products,from both local and foreign sources,for lowering blood glucose at home and their application in supplementary hypoglycemic foods.The key findings and conclusions suggest that there are various known T2DM-inducing factors,including genetic and environmental factors and three types of hybrid factors.

Structure-Based Optimization and Biological Evaluation of Pancreatic Lipase Inhibitors as Novel Potential Antiobesity Agents

The unusual fused b-lactone vibralactone was isolated from cultures of the basidiomycete Boreostereum vibrans and has been shown to significantly inhibit pancreatic lipase.In this study,a structure-based lead optimization of vibralactone resulted in three series of 104 analogs,among which compound C1 exhibited the most potent inhibition of pancreatic lipase,with an IC50 value of 14 nM.This activity is more than 3000-fold higher than that of vibralactone.The effect of compound C1 on obesity was investigated using high-fat diet(HFD)-induced C57BL/6 J obese mice.Treatment with compound C1 at a dose of 100 mg/kg significantly decreased HFD-induced obesity,primarily through the improvement of metabolic parameters,such as triglyceride levels.

Natural products in cosmetics

The global cosmetics market reached US$500 billion in 2017 and is expected to exceed US$800 billion by 2023,at around a 7%annual growth rate.The cosmetics industry is emerging as one of the fastest-growing industries of the past decade.Data shows that the Chinese cosmetics market was US$60 billion in 2021.It is expected to be the world’s number one consumer cosmetics market by 2050,with a size of approximately US$450 billion.The influence of social media and the internet has raised awareness of the risks associated with the usage of many chemicals in cosmetics and the health benefits of natural products derived from plants and other natural resources.As a result,the cosmetic industry is now paying more attention to natural products.The present review focus on the possible applications of natural products from various biological sources in skin care cosmetics,including topical care products,fragrances,moisturizers,UV protective,and anti-wrinkle products.In addition,the mechanisms of targets for evaluation of active ingredients in cosmetics and the possible benefits of these bioactive compounds in rejuvenation and health,and their potential role in cosmetics are also discussed.

Antiaging agents: safe interventions to slow aging and healthy life span extension

Human longevity has increased dramatically during the past century.More than 20%of the 9 billion population of the world will exceed the age of 60 in 2050.Since the last three decades,some interventions and many preclinical studies have been found to show slowing aging and increasing the healthy lifespan of organisms from yeast,flies,rodents to nonhuman primates.The interventions are classified into two groups:lifestyle modifications and pharmacological/genetic manipulations.Some genetic pathways have been characterized to have a specific role in controlling aging and lifespan.Thus,all genes in the pathways are potential antiaging targets.Currently,many antiaging compounds target the calorie-restriction mimetic,autophagy induction,and putative enhancement of cell regeneration,epige-netic modulation of gene activity such as inhibition of histone deacetylases and DNA methyltransferases,are under development.It appears evident that the exploration of new targets for these antiaging agents based on biogeron-tological research provides an incredible opportunity for the healthcare and pharmaceutical industries.The present review focus on the properties of slow aging and healthy life span extension of natural products from various biologi-cal resources,endogenous substances,drugs,and synthetic compounds,as well as the mechanisms of targets for antiaging evaluation.These bioactive compounds that could benefit healthy aging and the potential role of life span extension are discussed.

Effect of Silane Coupling Agent Concentration on Interfacial Properties of Basalt Fiber Reinforced Composites

The purpose of this study is to investigate the effect of the concentration of silane coupling solution on the tensile strength of basalt fiber and the interfacial properties of basalt fiber reinforced polymer composites.The surface treatment of basalt fibers was carried out using an aqueous alcohol solution method.Basalt fibers were subjected to surface treatment with 3-Methacryloxypropyl trimethoxy silane at 0.5 wt.%,1 wt.%,2 wt.%,4 wt.%and 10 wt.%.The basalt monofilament tensile tests were carried out to investigate the variation in strength with the concentration of the silane coupling agent.The microdroplet test was performed to examine the effect of the concentration of the silane coupling agent on interfacial strength of basalt reinforced polymer composites.The film was formed on the surface of the basalt fiber treated silane coupling agent solution.The tensile strength of basalt fiber increased because the damaged fiber surface was repaired by the firm of silane coupling agent.The firm was effective in not only the surface protection of basalt fiber but also the improvement on the interfacial strength of fiber-matrix interface.However,the surface treatment using the high concentration silane coupling agent solution has an adverse effect on the mechanical properties of the composite materials,because of causing the degradation of the interfacial strength of the composite materials.

基于“资源-资产-资本-资金”转化路径的森林碳汇价值实现机制

森林碳汇价值的实现是全民所有自然资源资产所有权委托代理机制试点工作中“保值增值”“落实权益”目标实现的重要组成部分。“资源-资产-资本-资金”转化路径是在自然资源资产价值实现困局、“绿水青山就是金山银山”理念、全民所有自然资源资产所有权委托代理试点要求中产生的,以实现自然资源资产收益为目标的价值实现路径。因森林碳汇具备“资源”“资产”“资本”“资金”的“四资”属性,该研究提出基于“资源-资产-资本-资金”转化的森林碳汇价值实现路径,从“资源-资产-资本-资金”转化路径视角厘清制约森林碳汇价值实现的障碍机理,发现:所有权委托代理机制不明晰的问题阻碍“资源”向“资产”转化,森林碳汇产业发展滞缓的现状遏制“资产”向“资本”转化,市场机制不健全的弊病掣肘“资本”向“资金”转化,最终导致了森林碳汇价值实现进程滞缓问题。基于此,该研究构建了以政府组织为主体的森林资源资产所有权委托代理机制,以森林碳汇产业为主体的森林碳汇产业支持制度,以市场平台为主体的森林碳汇市场交易制度,共同构筑出“资源-资产-资本-资金”转化与所有者权益落实目标双向交叉赋能、协同推进的森林碳汇价值实现多维制度体系,以森林碳汇价值实现为撬动点,对明晰森林资源资产管理权责、推进资产高效配置和保值增值、显化资产所有者收益问题进行了探索,以期为自然资源资产管理制度改革提供新思路。

一种新型绿色汞清洗剂的应用研究

主要研究了一种二烷基二硫代次膦酸盐和乙醇组成的汞清洗剂,利用二烷基二硫代次膦酸盐与汞形成配位化合物、采用乙醇作为溶剂体系,在溶剂和配位体作用下,可以让大汞珠转变为细微的配位体颗粒物,分散于乙醇中,无搅拌情况下剥离沉积在壁面的汞,并实现了对沉积于设备内壁的汞的清洗。该工艺的含汞配位体通过简单过滤实现与清洗剂分离,汞清洗剂可循环利用,含汞物可作固废处理,而且所用的清洗剂不腐蚀设备,是一种绿色汞清洗剂。分析了影响洗汞效果的各种因素,得到了最优的洗汞工艺:2%的浓度,保持中性或弱碱性,室温处理,漫灌浸泡不少于6hr。

恒粘剂对微生物凝固新鲜天然胶乳制备的恒粘天然橡胶性能的影响

研究恒粘剂(盐酸羟胺、硫酸羟胺、水合联胺、盐酸氨基脲和苯胺)对微生物凝固新鲜天然胶乳制备的恒粘天然橡胶(NR)性能的影响。结果表明:随着恒粘NR的盐酸羟胺和硫酸羟胺含量的增大,胶料的t90先延长后缩短,硫化速率(Vc)先减小后增大;随着恒粘NR的水合联胺和盐酸氨基脲含量的增大,胶料的t90延长,Vc减小;随着恒粘NR的苯胺含量的增大,胶料的ts2延长,t90先延长后缩短。随着恒粘NR的盐酸羟胺和硫酸羟胺含量的增大,胶料的300%定伸应力和拉伸强度减小;对于含水合联胺的恒粘NR胶料,随着水合联胺含量的增大,胶料的拉伸强度增大,但小于空白样;当恒粘NR的盐酸氨基脲和苯胺含量为0.05%~0.10%时,胶料可获得较大的拉伸强度和拉断伸长率。

基于Multi-agent技术的Web文本挖掘模型及应用

介绍了一个基于Multi-agent技术的Web文本挖掘模型,该模型利用多智能体技术,将文本挖掘和多维文件分析技术结合起来实现了文档收集、预处理、分类、聚类等功能。最后给出了根据该模型设计和实现的某企业人才素质评价系统的实例,系统运行结果证明了模型的有效性和科学性。

天然橡胶/三元乙丙橡胶并用胶辐射交联制备及其耐热空气老化性能

针对天然橡胶(NR)/三元乙丙橡胶(EPDM)并用胶共混效果不佳和耐老化性能较差的问题,本研究采用辐射交联技术制备了天然橡胶/三元乙丙橡胶并用胶,通过与热交联制备的并用胶对比,明确了辐射交联工艺对共混效果的促进作用。重点分析了NR/EPDM共混胶中生胶并用比和辐射交联等因素对老化前后并用胶力学性能的影响规律。热空气老化前,随着EPDM占比的增大,热交联样品的初始拉伸强度和伸长率曲线呈先降低后上升趋势,而辐射交联样品初始拉伸强度和伸长率呈线性下降趋势,说明辐照处理改善了EPDM/NR并用胶初始力学性能,辐射交联提高了NR和EPDM分子之间交联结构的完善性。热空气老化后,辐射交联样品的性能下降幅度小于热交联的样品,说明在热交联基础上,引入辐射技术可以提升辐射交联样品热老化后的伸长率保持率,尤其是在NR占比较大的情况下,辐射样品性能下降幅度能减小约50%。由此说明,利用辐射交联技术制备天然橡胶/三元乙丙橡胶并用胶具有比传统热硫化交联具有更好的耐热空气老化性能。

天然气工业用户峰谷分时定价Multi-Agent仿真

引入多智能体建模方法,构建了政府、用户、燃气公司、实时监控和人机交互等5类智能体,通过智能体的协助与交互模拟由于价格变化所引起的城市天然气管网需求与运营的动态变化过程。并且以某地区为例,将1天24小时划分为峰、平、谷3个时段,按照"量大价高"的原则实施分时定价政策,模拟该地区天然气管网的运行状态。结果表明:①实施天然气峰谷分时,定价能够在保证用户和燃气公司同时获益的情况下,有效降低峰谷负荷差;②在峰、平、谷价格比例逐渐增加的过程中,用户收益是单调递增的,而燃气公司的收益是先减少后增加的,当价格比例增加到一定程度后,燃气公司才开始获益。

全民所有自然资源资产所有权委托代理监管机制研究

文章归纳了行政委托代理理论在中国的发展历程,分析了全民所有自然资源资产所有权委托代理机制的形成背景、运行机制及其双重属性,同时研究剖析自然资源资产委托代理机制实践,指出当前监管机制的不足之处。研究显示:监管机制中存在“监管轻视”“违规再委托”“权利残缺”等问题,其原因在于监管角色不明确和监管模式缺陷。基于此,提出通过探索厘清监管角色、改善监管模式等方式,完善全民所有自然资源资产所有权委托代理监管机制的建议。

基于多Agent的战场角色仿真建模研究

作战仿真系统模型的复杂性主要来源于战场角色行为和战场环境的复杂性,多Agent系统是解决复杂问题的有效方法。分析作战仿真系统的模型组成和特点,结合自然环境建模,研究了基于多Agent的战场角色建模方法,描述了战场角色Agent所需的组件及其功能。设计了一种面向战场角色建模的通用Agent体系结构,并对战场角色Agent的规划、通信和协作等理论和应用问题进行了研究。

石榴皮染料在棉织物环保染色中的应用

针对石榴皮色素在棉织物染色中存在的低色牢度、金属媒染剂和化学固色剂导致环境污染以及人体危害等问题,通过优化石榴皮直接染色棉织物的染色工艺,选择3种天然媒染剂和3种金属媒染剂以不同媒染方式染色。利用天然松香固色剂对染色后的棉织物进行固色处理,探讨天然媒染剂提高织物染色性能的可行性,评估松香天然固色剂的固色效果以及不同染色工艺对石榴皮染色棉织物的染色性能的影响。结果表明,石榴皮直接染色棉织物最佳工艺:温度为80℃,染色时间为90min,pH值为7.0;经天然媒染剂媒染(茶卡盐后媒染)的织物可达到最大K/S值(7.64);经固色后染色棉织物的K/S值可提高至10.23,色牢度最高可达4~5级、5级;染色棉织物经过不同的染色工艺,可呈现不同的色相。