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1.
煤矿生产过程中伴生的大量煤矸石不仅占用土地资源,而且在露天堆放的过程中其含有的有害微量元素汞、砷等会进入自然环境中,对环境造成严重污染。通过总结,介绍了国内外学者对于煤矸石中汞、砷的研究成果。主要从煤矸石中汞、砷含量,煤矸石加热汞、砷释放,煤矸石中汞、砷淋溶析出以及煤矸石中汞、砷赋存形态四个方面进行总结。以期为更多学者对于煤矸石中汞、砷的研究工作提供一定的帮助。  相似文献   

2.
在BB肥中加入中、微量元素的必要性   总被引:1,自引:0,他引:1  
在BB肥中加入中、微量元素是测土配方施肥的需要。阐明了BB肥中加入中、微量元素的必要性、有效性、合法性以及对土壤和农作物的针对性,加入中、微量元素的BB肥可提高肥料利用率,提高农作物的产量和品质,减少病害的发生,具有广阔的发展前景。  相似文献   

3.
《弹性体》2009,19(5):85-90
煤焦油中馏分常温脱色除臭技术 煤焦油中馏分,是指中、低、高温煤焦油经蒸馏切割210-300℃馏分段的液体油,一般称中馏分油。此类油经脱酚、脱萘后,外观颜色为黑色,伴有刺激性臭味,其胶质、残炭、焦油酸、碱都含量高,着火性能差、粘度小、不稳定,不能直接被利用。自1985年开始,就针对煤焦油中馏分脱色除臭的老大难问题进行攻关,  相似文献   

4.
建立高效液相色谱法测定大鼠组织样品中没食子酸乙酯的含量,研究其在大鼠体内的分布特征。在灌胃给药后10min、30min、2h,解剖取心、肝、脾、肺、肾、胃、小肠组织,采用高效液相色谱法测定各组织中没食子酸乙酯的浓度。结果表明,没食子酸乙酯在大鼠体内分布广泛,以肝脏中分布最多,其次为肺、脾、心,在胃中分布最低,给药2h后肾脏中浓度显著增加。本研究方法简便、灵敏、准确,可用于大鼠组织中没食子酸乙酯含量的测定。  相似文献   

5.
分别从中国煤中硒的丰度、赋存状态和有机亲和性、迁移性和环境效应3个方面讨论了煤中硒的研究概况。硒在煤中相对于地壳中富集,不同地区、不同成煤期,煤中硒的含量差异很大;煤中硒大部分以有机结合态存在,无机结合态的硒大多数存在于黄铁矿中;在燃烧过程中,硒主要以气态的形式进入大气,或被极细飞灰吸附,污染环境,危害人体健康。  相似文献   

6.
旱天放江是造成上海市城区河道污染的主要原因之一。以虬江为研究对象,探究分流制泵站旱天放江后,调水对受纳河道水质的影响。选取放江当天至调水第7 d,分析对比受纳水体上游至下游,各采样断面水体中COD、TP、氨氮以及沉积物中TOC含量的差异。结果表明,放江后和调水连续7 d后,各断面水体中水质检测指标以及沉积物中TOC含量均高于放江前。放江开始至调水第7 d,虬江水体中COD、TP、氨氮含量均呈现先递减后趋向于平稳的趋势,沉积物中TOC含量呈现递增的趋势。受调水作用的影响,上游水体中COD、TP、氨氮以及沉积物中TOC含量均低于下游。  相似文献   

7.
《化工科技》2009,17(4):68-73
煤焦油中馏分常温脱色除臭技术 煤焦油中馏分,是指中、低、高温煤焦油经蒸馏切割210~300℃馏分段的液体油,一般称中馏分油。此类油经脱酚、脱萘后,外观颜色为黑色,伴有刺激性臭味,其胶质、残炭、焦油酸、碱都含量高,着火性能差、粘度小、不稳定,不能直接被利用。  相似文献   

8.
化肥生产中,原料气经转化、变换、脱碳、合成氨的流程是当今世界合成氨的经典生产工艺。作为脱碳单元的关键设备,溶液泵在合成氨生产中占有重要位置,是脱碳生产装置中不可缺少的设备。在实际工作中,也常常因为脱碳溶液泵故障而危及安全生产。  相似文献   

9.
甘油近期市场行情分析   总被引:1,自引:0,他引:1  
甘油又名丙三醇,它在医药、食品、化工等领域都有着广泛的用途。在医药领域主要用于抗菌防腐剂、柔和剂、保湿剂、增塑剂、溶剂、甜味剂等,广泛应用于口服、耳、眼、局部和肠道给药制剂。甘油在不同类型的药物制剂中起着不同的作用,如在乳膏、乳剂等局部用药制剂中用作保湿剂和柔和剂,在注射剂中被用于溶剂,在口服溶液制剂中则被用作溶剂、甜味剂、抗菌防腐剂、增稠剂等,在明胶软胶囊、膜包衣和明胶栓剂中还可用作增塑剂。  相似文献   

10.
选取孝感市污水处理厂的污泥为研究对象,测定了污泥中重金属Zn、Cu、Cr、Cd、Pb的总量及其各形态的含量,并对各形态进行分析。结果表明,孝感市污水处理厂的城市污泥中5种重金属元素的含量大小依次为CrZnCuPbCd。均低于《农用污泥中污染物控制标准》(GB4284-84)中污泥农用的碱性标准,所以该污泥适合用于p H6.5的土壤作为农用处置。Zn、Cu、Cr、Cd、Pb在该污泥中主要以残渣态和有机结合态存在,不易释放到环境中。  相似文献   

11.
油樟和樟树化学型中的芳樟、龙脑樟是中国特色樟科树种,总面积约8万公顷,主要分布在四川宜宾、四川广安、江西赣州、广西南宁、湖南新晃等地.樟树叶油中的1,8-桉叶素、芳樟醇和天然龙脑是重要的出口产品,也是医药、香精香料和日化行业的主要原料.本文综述了樟树资源特征、分布,介绍了油樟油、芳樟油、龙脑樟油的化学组成和生物活性,樟...  相似文献   

12.
Biosorption may be simply defined as the removal of substances from solution by biological material. Such substances can be organic and inorganic, and in gaseous, soluble or insoluble forms. Biosorption is a physico‐chemical process and includes such mechanisms as absorption, adsorption, ion exchange, surface complexation and precipitation. Biosorption is a property of both living and dead organisms (and their components) and has been heralded as a promising biotechnology for pollutant removal from solution, and/or pollutant recovery, for a number of years, because of its efficiency, simplicity, analogous operation to conventional ion exchange technology, and availability of biomass. Most biosorption studies have carried out on microbial systems, chiefly bacteria, microalgae and fungi, and with toxic metals and radionuclides, including actinides like uranium and thorium. However, practically all biological material has an affinity for metal species and a considerable amount of other research exists with macroalgae (seaweeds) as well as plant and animal biomass, waste organic sludges, and many other wastes or derived bio‐products. While most biosorption research concerns metals and related substances, including radionuclides, the term is now applied to particulates and all manner of organic substances as well. However, despite continuing dramatic increases in published research on biosorption, there has been little or no exploitation in an industrial context. This article critically reviews aspects of biosorption research regarding the benefits, disadvantages, and future potential of biosorption as an industrial process, the rationale, scope and scientific value of biosorption research, and the significance of biosorption in other waste treatment processes and in the environment. Copyright © 2008 Society of Chemical Industry  相似文献   

13.
Over the last years, different nanomaterials have been investigated to design highly selective and sensitive sensors, reaching nano/picomolar concentrations of biomolecules, which is crucial for medical sciences and the healthcare industry in order to assess physiological and metabolic parameters. The discovery of graphene (G) has unexpectedly impulsed research on developing cost-effective electrode materials owed to its unique physical and chemical properties, including high specific surface area, elevated carrier mobility, exceptional electrical and thermal conductivity, strong stiffness and strength combined with flexibility and optical transparency. G and its derivatives, including graphene oxide (GO) and reduced graphene oxide (rGO), are becoming an important class of nanomaterials in the area of optical and electrochemical sensors. The presence of oxygenated functional groups makes GO nanosheets amphiphilic, facilitating chemical functionalization. G-based nanomaterials can be easily combined with different types of inorganic nanoparticles, including metals and metal oxides, quantum dots, organic polymers, and biomolecules, to yield a wide range of nanocomposites with enhanced sensitivity for sensor applications. This review provides an overview of recent research on G-based nanocomposites for the detection of bioactive compounds, providing insights on the unique advantages offered by G and its derivatives. Their synthesis process, functionalization routes, and main properties are summarized, and the main challenges are also discussed. The antioxidants selected for this review are melatonin, gallic acid, tannic acid, resveratrol, oleuropein, hydroxytyrosol, tocopherol, ascorbic acid, and curcumin. They were chosen owed to their beneficial properties for human health, including antibiotic, antiviral, cardiovascular protector, anticancer, anti-inflammatory, cytoprotective, neuroprotective, antiageing, antidegenerative, and antiallergic capacity. The sensitivity and selectivity of G-based electrochemical and fluorescent sensors are also examined. Finally, the future outlook for the development of G-based sensors for this type of biocompounds is outlined.  相似文献   

14.
Liquid silicone rubber (LSR) is an elastomer molded into critical performance components for applications in medical, power, consumer, automotive, and aerospace applications. This article reviews process behavior, material modeling, and simulation of the (LSR) injection molding process. Each phase of the LSR injection molding process is discussed, including resin handling, plastication, injection, pack and hold, and curing; and factors affecting the molding process are reviewed. Processing behavior of LSR is marked by transient interactions between curing, shear rate, temperature, pressure, and tooling. Therefore, current LSR models for curing, viscosity, pressure, and temperature are discussed. Process dynamics and material modeling are combined in LSR injection molding simulations with applications in mold design, troubleshooting process-induced defects, and management of shear stress and non-uniform temperatures between LSR and substrates during overmolding. Finally, case studies using commercial simulation software are presented, which have shown cavity pressure and flow front advancement within 3% of experimental values. Optimization of LSR materials, data collection, model fitting, venting, and bonding remain areas of continued interest.  相似文献   

15.
Polyvinylidene fluoride (PVDF) is a semicrystalline thermoplastic and electroactive polymer with piezoelectric and pyroelectric properties, thermal stability, elasticity, and chemical resistance. PVDF exits in five different phases (α, β, δ, γ, and ε-phase). Unique properties of this polymer enhances its use in chemical, biomedical, and electronic industries such as supercapacitors, transducers, actuators, and batteries. Carbon nanotube (CNT) is used as reinforcement to exploit full potential of PVDF in energy, electronics, and membrane technology. The nanofiller affects morphology, piezoelectric, pyroelectric, electrical, dielectric, thermal, and mechanical properties of PVDF-based nanocomposite. CNT content and chemical modification influence properties as well as application of PVDF.  相似文献   

16.
Chromogranin A (CgA), B (CgB), and C (CgC), the family members of the granin glycoproteins, are associated with diabetes. These proteins are abundantly expressed in neurons, endocrine, and neuroendocrine cells. They are also present in other areas of the body. Patients with diabetic retinopathy have higher levels of CgA, CgB, and CgC in the vitreous humor. In addition, type 1 diabetic patients have high CgA and low CgB levels in the circulating blood. Plasma CgA levels are increased in patients with hypertension, coronary heart disease, and heart failure. CgA is the precursor to several functional peptides, including catestatin, vasostatin-1, vasostatin-2, pancreastatin, chromofungin, and many others. Catestatin, vasostain-1, and vasostatin-2 suppress the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in human vascular endothelial cells. Catestatin and vasostatin-1 suppress oxidized low-density lipoprotein-induced foam cell formation in human macrophages. Catestatin and vasostatin-2, but not vasostatin-1, suppress the proliferation and these three peptides suppress the migration in human vascular smooth muscles. Chronic infusion of catestatin, vasostatin-1, or vasostatin-2 suppresses the development of atherosclerosis of the aorta in apolipoprotein E-deficient mice. Catestatin, vasostatin-1, vasostatin-2, and chromofungin protect ischemia/reperfusion-induced myocardial dysfunction in rats. Since pancreastatin inhibits insulin secretion from pancreatic β-cells, and regulates glucose metabolism in liver and adipose tissues, pancreastatin inhibitor peptide-8 (PSTi8) improves insulin resistance and glucose homeostasis. Catestatin stimulates therapeutic angiogenesis in the mouse hind limb ischemia model. Gene therapy with secretoneurin, a CgC-derived peptide, stimulates postischemic neovascularization in apolipoprotein E-deficient mice and streptozotocin-induced diabetic mice, and improves diabetic neuropathy in db/db mice. Therefore, CgA is a biomarker for atherosclerosis, diabetes, hypertension, and coronary heart disease. CgA- and CgC--derived polypeptides provide the therapeutic target for atherosclerosis and ischemia-induced tissue damages. PSTi8 is useful in the treatment of diabetes.  相似文献   

17.
《Ceramics International》2023,49(20):32343-32358
The many branches of nanoscience have made significant strides and advancements during the past ten years, as has the entire scientific community. Zirconia nanoparticles have several uses as adsorbents, nanosensors, nanocatalysts, and other types of nanomaterials. Their outstanding biomedical uses in dental care and drug delivery, as well as their intriguing biological characteristics, such as their anti-cancer, anti-microbial, and antioxidant activity, have further encouraged researchers to investigate their physicochemical properties using various synthetic pathways. Due to the popularity of zirconia-based nanomaterials, the current research comprehensively examines several synthesis techniques and their effects on the composition, dimensions, forms, and morphologies of these nanomaterials. In general, there are two methods for creating zirconia nanoparticles: chemical synthesis, which uses hydrothermal, solvothermal, sol-gel, microwave, solution combustion, and co-precipitation processes; and a greener method, which uses bacteria, fungi, and plant components. The aforementioned techniques have been evaluated in the present review for achieving particular phases and shapes. A thorough analysis of zirconia-based nanomaterial's uses is also included in the review. Furthermore, comparisons with their equivalent composites for various applications as well as the influence of particular phases and morphologies have been added. The final portion includes the summary, future outlook, and potential application.  相似文献   

18.
建筑陶瓷装饰技术的现状及发展趋势   总被引:2,自引:1,他引:2  
俞康泰  刘儒平 《陶瓷学报》2006,27(3):304-308
简要介绍了建筑陶瓷领域、日用陶瓷和工艺美术陶瓷领域装饰技术的最新进展,着重介绍了引领陶瓷装饰技术发展和最新潮流的意大利、西班牙在这方面的水平和成果,他们为开放的中国从世界陶瓷大国尽快过渡到世界陶瓷强国提供了借鉴和方向。装饰技术的总体水平包括设计、装饰技法、装饰工艺、装饰材料和装饰机械装备等几大方面,其中设计是龙头,它应包括产品的图案设计、造型设计、色彩的搭配、产品的应用及展示设计等多个方面;装饰技法包括平面装饰和立体装饰、平铺和点缀、多种装饰材料的交替和组合应用等;装饰工艺包括布料(多管布料、多次布料、随机布料、微粉和干粒布料),丝网印刷(平面丝网印刷、辊筒印刷、胶辊印刷),各种施釉工艺,抛光,柔抛,釉抛和半釉抛工艺,磨边和水刀切割,拼花工艺等;装饰材料有各种色料、成釉、金属釉、干粒、印油、渗花液、喷墨印刷用耗材等;装饰机械装备包括各种装饰机械和工模具。  相似文献   

19.
针对油田套管损坏情况日益严重的现状,进行了套管损坏类型、特点及套损机理研究,形成了配套完善的套损防治技术体系。完善了从钻井、完井、固井及开发生产全过程的套损预防与保护系列技术,形成了以修胀套、爆炸整形、打通道、套管加固、取换套、侧钻为主的系列套管修复技术以及以工程测井为主的套管状况检测系列技术。并由实践认识到:只有坚持预防为主,研、防、治并举,建立适合不同油藏类型、不同开发阶段、不同开发方式的套损综合防治模式,才能解决油田套管损坏问题。  相似文献   

20.
张军  贾悦  刘博  张则俊  安静  蔡贤明 《化工进展》2020,39(z2):372-378
集输过程中的含油污泥具有成分复杂、含液率高、乳化胶结稳定等特性,占油田危险废物新增量的约60%,是污染防治的重点。近年来,学者们开展了大量“调质-固液分离”减量化技术降低其环境风险和处置成本,但仍存在需要针对含油污泥不同来源优选相匹配的减量化调质方法和装置的难题。为此,本文回顾了氧化、破乳、絮凝、干化/半干、超声波、微波等化学与物理调质方法,离心机、叠螺机、压滤机3种固液分离装置研究进展,通过分别对各种调质方法及装置的对比分析,重点阐述了其作用机理、优缺点、适用对象。其中化学调质方法中破乳氧化、加酸更适用于高含聚油泥;表面活性剂破乳需加热,可与超声波相结合;有机和无机絮凝剂配合可提高罐底泥中油回收效果;干化/半干化法受经济效益制约。在文献基础上,认为未来应加强生物表面活性剂、生物电化学系统、椭圆叠螺机、基于固液分离装置数值模型基础上的设计与优化软件、多学科相结合的减量化耦合技术研究。  相似文献   

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