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1.
具有生物活性的喹啉类化合物的研究进展   总被引:2,自引:0,他引:2  
概述了具有生物活性的喹啉类化合物的研究进展.根据结构特点分为4-羟基喹啉、6-羟基喹啉、8-羟基喹啉、4-胺(肼)基喹啉、喹啉酰胺、喹啉酮、二氯喹啉酸衍生物及其他等8类化合物,对其生物活性进行综述,介绍了部分农药品种的合成方法.  相似文献   

2.
陈黎明 《广东化工》2006,33(6):31-32
在市场经济条件下,矿山必须适应市场和满足用户要求,以好的产品质量来赢得用户和占领市场。提高产品质量关键在于控制矿石品位及杂质等指标的稳定性,出口硫铁矿(以下简称“出口矿”)除了S、Fe、Pb、Zn、Cu、SiO2、C、H2O、粒度的指标控制外,个别客户还要求pH在5~6之间,而我们出口矿S品位在45~48以上的pH一般在2~4之间,为满足客户的需求,我们必须降低出口矿的酸度即提高pH,这关系到配矿的工艺流程。  相似文献   

3.
用水煮法提取了天然茶叶染料,研究了茶叶色素的吸收光谱。对固液比、提取温度、浸提剂酸度、反应时间等提取条件进行了研究,并测定了色素在不同pH、温度等条件下的稳定性。结果表明,提取茶叶色素的最佳工艺条件为固液比1∶20,在沸煮(100℃)的条件下提取50分钟。该色素受pH影响较明显,对氧化剂、还原剂较敏感,但耐热稳定性较好。金属离子Ca2+、Cu2+、Zn2+、Mg2+、Na+、K+、Pb2+、Sn2+、Ni2+的存在对色素色泽基本无影响,Al3+、Fe2+、Fe3+的存在对色素有不良影响。茶叶色素易溶于水、乙醇、低浓度乙酸等极性溶液,不溶于苯、丙酮、氯仿、乙醚等非极性溶剂,属水溶性色素。  相似文献   

4.
亲水性树脂的合成与亲水性的研究   总被引:1,自引:0,他引:1  
以含有-CONHCH_2OH、-CONH_2、-COOH、-COOROH、-NH_2、-OH、-SO_3H等亲水性基团的树脂为成膜物质,制备空调机热交换器的铝翅片面层保护膜。研究了各种基团树脂的亲水性,以及pH值、成膜温度、成膜时间、涂膜厚度、表面活性剂等对膜的亲水性的影响。  相似文献   

5.
针对某电厂的超滤给水泵流量、超滤给水泵的变频设计、超滤系统的流量分配、超滤顺控以及相关现象进行分析总结,对超滤进水气动调阀的调节、超滤再循环门的关门时间的优化、超滤给水泵的流量曲线比对,解决相关问题,保证了超滤系统正常、有效、经济的运行。  相似文献   

6.
高邦仁  王煜全 《发现》2010,(11):54-56
来来的家没有冷冰冰的技术味——你甚至看不到一根缠绕的电线或者嵌在墙壁上的开关,互联网、DVD、视频、电话线和闭路电视通过隐藏的布线系统分布在各个房间;保安系统、暖气、浴室里的加热手巾架、空调、大厅音乐、视频分布器、房门开关都被无线智能装置控制……  相似文献   

7.
磷酸锌钾的形貌控制的研究   总被引:1,自引:0,他引:1  
袁爱群 《应用化工》2006,35(4):252-254
在以硝酸锌、磷酸、氢氧化钾为原料制备磷酸锌钾工艺中,考察了六种表面活性物质对产物颗粒形貌的影响。结果显示,通过添加不同表面活性物质如十二烷基苯磺酸钠、聚丙烯酰胺、OP-10、CTAB、N,N-二甲基酰胺或三乙醇胺可以制备从棉絮状、团块状、层状、片状、圆片状或者层柱状且大小不一的晶体。初步探讨了表面活性物质对磷酸锌钾形貌的控制机理。  相似文献   

8.
国家工程建设发展显著促进了对大型桥梁、工程设施、装备等需求,多数装备设施处于腐蚀环境中,而有效的防护手段可避免或减缓腐蚀过程。综述了金属材料防腐蚀的主要有效手段,包括防护涂层、缓蚀剂、电化学保护等方法。今后可在防腐材料开发和制备工艺上,进一步降低生产成本、优化工艺操作、减少环境危害,实现防腐材料的绿色、可持续性发展。  相似文献   

9.
本文主要介绍了合成氨技术发展历程和基本状况,分析了生产过程中采用的典型工艺及其技术特点与经济性,指出了合成氨技术可能的发展趋势。介绍了高油价下合成氨的原料结构变化及相关技术进展,认为未来合成氨技术进展的主要趋势是大型化、低能耗、结构调整、清洁生产、长周期运行。  相似文献   

10.
李晶晶 《河南化工》2010,27(4):99-100
随着风电机组技术水平的不断提升,风电机组发展趋势为:单机容量不断提高、风电机组型式多元化、风电机组关键部件技术不断发展、风电机组设计技术趋向成熟、风电机组制造技术智能化、风电机组可利用率不断提高。  相似文献   

11.
树脂基复合材料成型工艺研究进展   总被引:3,自引:0,他引:3  
主要综述了树脂基复合材料的几种成型工艺,包括RTM、VARTM、CRTM、LRTM、RFI、VARI、SCRIMP、SRIM、TERM,各自的发展现状、成型原理、特点等.  相似文献   

12.
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   

13.
《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   

14.
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   

15.
Electrospinning jets and polymer nanofibers   总被引:4,自引:0,他引:4  
In electrospinning, polymer nanofibers are formed by the creation and elongation of an electrified fluid jet. The path of the jet is from a fluid surface that is often, but not necessarily constrained by an orifice, through a straight segment of a tapering cone, then through a series of successively smaller electrically driven bending coils, with each bending coil having turns of increasing radius, and finally solidifying into a continuous thin fiber. Control of the process produces fibers with nanometer scale diameters, along with various cross-sectional shapes, beads, branches and buckling coils or zigzags. Additions to the fluid being spun, such as chemical reagents, other polymers, dispersed particles, proteins, and viable cells, resulted in the inclusion of the added material along the nanofibers. Post-treatments of nanofibers, by conglutination, by vapor coating, by chemical treatment of the surfaces, and by thermal processing, broaden the usefulness of nanofibers.  相似文献   

16.
收集了2010年7月~2011年6月世界塑料工业的相关资料,介绍了2010~2011年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、不饱和聚酯树脂、环氧树脂、聚氨酯)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。  相似文献   

17.
Even though several plants can improve the female reproductive function, the use of herbs, herbal preparations, or essential oils during pregnancy is questionable. This review is focused on the effects of some essential oils and their constituents on the female reproductive system during pregnancy and on the development of the fetus. The major concerns include causing abortion, reproductive hormone modulation, maternal toxicity, teratogenicity, and embryo-fetotoxicity. This work summarizes the important studies on the reproductive effects of essential oil constituents anethole, apiole, citral, camphor, thymoquinone, trans-sabinyl acetate, methyl salicylate, thujone, pulegone, β-elemene, β-eudesmol, and costus lactone, among others.  相似文献   

18.
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   

19.
2004~2005年国外塑料工业进展   总被引:1,自引:0,他引:1  
收集了2004年7月-2005年6月国外塑料工业的相关资料,介绍了2004年~2005年国外塑料工业的发展情况。提供了世界几大区域塑料的产量、增长率及所占份额;美国、德国、日本、韩国、法国、比利时、印度、西班牙、中国台湾、加拿大、巴西、英国等国家和地区的不同树脂的产量及消费量;各国、各地区塑料原料的产量、进出口量、国内消费量和人均消费量;日本塑料原料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮、聚砜)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

20.
最近二十多年,由于新型碳材料(包括富勒烯、碳纳米管和石墨烯等)在很多方面具有优异的性能,开辟了诸多新颖的应用领域。本文综述了碳纳米管和石墨烯在聚烯烃树脂中的应用,通过物理共混和原位合成法形成复合材料,提高了聚烯烃材料的力学性能、结晶和熔融性能、热稳定性和导电性等,复合材料在场发射显示器件、储氢材料、电池、超强超韧复合材料、显微镜探头、超级电容器、电子枪、纳米电子器件、传感器等诸多领域已取得了较大的突破。  相似文献   

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