反渗透技术在高纯水生产中的应用

简述了反渗透原理;详细介绍了反渗透法和离子交换法相结合生产高纯水工艺装置运行情况,给出了运行中出现问题的解决办法;总结得出反渗透装置能否长期稳定运行,很大程度上取决于预处理装置的设计和操作参数的控制。     

化肥装置用材与工艺的分析

通过对九江化肥装置材料选择、使用条件、腐蚀机理的分析,结合类似装置曾发生的设备损坏事故,对装置运行中工艺参数条件控制的若干方面进行了讨论,以延长设备使用寿命,保证安全稳定生产。     

多变量控制方式在液氮洗工艺中的应用

针对液氮洗装置的工艺特点,通过对合成氨装置生产工艺和过程控制以及历史数据的采集分析,对被控变量进行预测控制与精准控制,保证被控变量在最优区间运行,成功将多变量控制方式应用于合成氨装置。不仅解决了装置多变量耦合性问题,也解决了氢氮比控制滞后问题,减小工艺参数波动,提高装置运行的稳定性。     

ITCC防喘振控制系统在离心式压缩机中的运用

在生产运行过程中,针对离心式压缩机受工艺参数及各种工况改变的诸多影响,容易发生喘振的问题.通过ITCC控制系统设定防喘振控制逻辑,采用先进的控制方式,最大限度地防止了机组喘振的发生,有效地防止事故,避免停车,从而保证装置安全稳定长周期运行.     

聚酯装置投料试车及运行总结

根据洛阳聚酯装置开工及实际运行情况,结合杜邦聚酯工艺技术特点,对本装置工艺流程,仪表控制系统,投料试车过程,装置试生产及生产达标进行了全面的阐述,通过对工艺条件及其控制的分析,阐明了本装置技术的成熟性及试生产过程参数的优化,为同类装置的开车及平稳生产提供了可靠的依据。     

10万吨/年干气脱硫装置运行分析

介绍了国内现在干气脱硫技术和延安石油化工厂10万吨/年干气脱硫装置运行情况,通过运行状况的分析以及工艺参数的调整,有效的控制精制干气总硫含量。在调整工艺参数的同时确保装置运行平稳,产品质量合格,最终将能耗降到最低,达到了预期的目标。     

25万t/a 硝酸铵装置建设及生产运行情况技术总结

介绍了25万t/a硝酸铵装置的生产工艺流程,并对工艺及设备进行了完善,提供了多孔(工业)硝酸铵装置工艺运行参数及质量与物料消耗参数,针对成品硝酸铵水分较高提出了改进措施。     

25万 t／a 硝酸铵装置建设及生产运行情况技术总结

介绍了25万t/a硝酸铵装置的生产工艺流程,并对工艺及设备进行了完善,提供了多孔（工业）硝酸铵装置工艺运行参数及质量与物料消耗参数,针对成品硝酸铵水分较高提出了改进措施。     

基于HAZOP的油页岩有氧干馏工艺装置安全分析

以HAZOP分析方法的理论和实际应用为基础,以油页岩有氧干馏工艺装置为例,对其生产过程中所涉及的设备及危险性进行了分析。该方法通过引导词并配合流程或设备中的工艺参数组成有实际意义的偏差来找出装置或流程中存在的危险因素。分析结果表明导致事故发生的主要工艺参数为通入干馏炉氧气浓度和干馏炉内床层温度。在油页岩有氧干馏装置运行中,控制氧气含量及反应器温度,是保障企业生产安全的重要因素之一。分析结果为有氧干馏装置本质安全设计提供一定的参考价值。     

快速浅层离子交换在除盐水水质控制中的应用

介绍了快速浅层离子交换装置的工艺特点以及在实际应用时的优劣势，并以石家庄某热电厂除盐水水质控制项目为例，阐述该离子交换装置在除盐水工艺中运行时的工艺流程、运行参数和处理效果。     

A review of ZrO2 nanoparticles applications and recent advancements

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.     

Semiochemistry of the Goldeneyed Lacewing Chrysopa oculata: Attraction of Males to a Male-Produced Pheromone

Gas chromatographic-electroantennographic detection (G3C-EAD) experiments showed that antennae of males and females of the goldeneyed lacewing, Chrysopa oculata Say (Co. = Chrysopa), consistently responded to four compounds extracted from the abdominal cuticle of males:nonanal, nonanol, nonanoic acid, and (1R*,2S*,5R*,8R*)-iridodial. These compounds were not detected from abdominal cuticle of females. Thoracic extracts of both sexes contained antennal-stimulatory 1-tridecene and EAD-inactive skatole. Chrysopa oculata adults were most sensitive to (1R,2S,5R,8R)-iridodial standard at an EAD-response threshold between 0.1 and 1 pg, which was 10-100 times lower than thresholds for nonanal and nonanoic acid, and up to 10,000 times lower than thresholds for other compounds tested. A similar EAD response pattern was also found in another Chrysopa sp. (Co. quadripunctata Burmeister). In field-trapping experiments, (1R,2S,5R,8R)-iridodial was the only male-specific compound that attracted Co. oculata males. Males also were weakly attracted to (1R,4aS,7S,7aR)-nepetalactol (an aphid sex pheromone component), probably due to the 5% (1R,2S,5R,8R)-iridodial present in the synthetic sample as an impurity. A herbivore-induced plant volatile, methyl salicylate, increased attraction of males to (1R,2S,5R,8R)-iridodial, whereas 1-tridecene was antagonistic. No females were caught in the entire study. Scanning electron micrographs revealed numerous male-specific, elliptical epidermal glands on the 3rd-8th abdominal sternites of Co. oculata, which are likely the pheromone glands. Another lacewing species, Chrysoperla rufilabris (Burmeister) (Cl. = Chrysoperla), did not produce male-specific volatiles or possess the type of gland presumed to produce pheromone in Co. oculata males, but (Z)-4-tridecene was identified as a major antennal-stimulatory compound from thoracic extracts of both sexes of Cl. rufilabris. Thus, (1R,2S,5R,8R)-iridodial (or its enantiomer) is now identified as a male-produced male aggregation pheromone for Co. oculata, the first pheromone identified for lacewings.     

The Emerging Roles of Chromogranins and Derived Polypeptides in Atherosclerosis,Diabetes, and Coronary Heart Disease

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.     

Graphene-Based Sensors for the Detection of Bioactive Compounds: A Review

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.     

A review of liquid silicone rubber injection molding: Process variables and process modeling

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.     

Using symmetry to understand the attributes of color

The common attributes of color are distinguishable by their symmetries. Hue, saturation, chroma, chromaticness, whiteness, and blackness symmetries are discussed. Symmetries are generally not sufficient to specify unique formulas for color attributes, nor are they an endorsement of color model accuracy. However, symmetries do provide constraints for valid formulae, which are useful even when symmetries are only approximate. They also provide an alternate conceptual understanding of color attributes that differs from standard color science definitions. Symmetries provide a simplified framework for calculating groups of colors that share color attributes. Color models examined include the Hunt Model, a simple color model (SCM), various CIE color spaces, and IPT. A general functional form describes symmetries and scaling laws for many color models, and exceptions are discussed. © 2007 Wiley Periodicals, Inc. Col Res Appl, 33, 27–44, 2008     

Potential of Polyvinylidene Fluoride/Carbon Nanotube Composite in Energy,Electronics, and Membrane Technology: An Overview

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.     

Pheromonal activity of single castoreum constituents in beaver,Castor canadensis

Behavioral activity of single components of beaver castoreum was demonstrated for the first time. In four experiments samples were presented to free-ranging beaver in their family territories. First, responses to whole castoreum and anal gland secretion (AGS) from males and females were tested. Second, 24 compounds, known to be constituents of beaver castoreum, were individually screened for activity. Four of these consistently released immediate responses during the observation periods. These are the phenols 4-ethylphenol and 1,2-dihydroxybenzene and the ketones acetophenone and 3-hydroxyacetophenone. In the most complete responses, the beaver sniffed from the water, were attracted to the odor, swam toward its source, went on land, and then approached, sniffed, pawed, and scent-marked the artificial scent mound. 4-Ethoxyphenol, a compound not yet found in castoreum, also released these responses. Five additional compounds resulted in a few delayed visits to the samples during the night following the observations, as evidenced by destroyed scent mounds. These are 4-methyl-1,2-dihydroxybenzene, 4-methoxyacetophenone, 5-methoxysalicylic acid, salicylaldehyde, and 3-hydroxybenzoic acid. Third, mixtures of 24 and six compounds were tested. Responses to these mixtures could be as strong as those to whole castoreum. Fourth, the four regularly active compounds were tested in two additional beaver populations and proved to be active there, too. The response was strongest in the densest beaver population.     

Enhancing the daytime conspicuity of pedestrians through the usage of fluorescent materials

The issue of daytime, pedestrian visibility, especially where occupational activities are involved, can be well served by bringing existing and related knowledge on high-visibility materials together with new product capabilities. Formulated strategically, this information can beneficially serve the personal safety of our society. This particular form of personal safety involves being seen, most critically, by operators of motorized vehicles. Therefore, the issues of visibility, visibility enhancement, and conspicuity are focused upon through the use of high-visibility materials. High-visibility materials include but are not limited to retroreflective forms. In daytime and dusk/dawn conditions, fluorescent-colored products can serve as high-visibility materials used to effectively generate enhanced conspicuity. the time has now come to more aggressively research what we may intuitively believe and then apply this knowledge. to more fully grasp what is involved, we must take into account the following: 1. a basic understanding of fluorescence, 2. basic human vision and perception, 3. situations calling for enhanced conspicuity, 4. strategies for use, 5. product development, 6. specfications, guidelines and standards, 7. public education, and awareness. © 1995 John Wiley & Sons, Inc.     

Analyses of Avocado (Persea americana) Nectar Properties and their Perception by Honey bees (Apis mellifera)

Honey bees are important avocado pollinators. However, due to the low attractiveness of flowers, pollination is often inadequate. Previous work has revealed that avocado honey is relatively unattractive to honey bees when compared with honey from competing flowers. We characterized avocado honey and nectar with respect to their odor, color, and composition of sugars, phenolic compounds, and minerals. Furthermore, we tested how honey bees perceive these parameters, using the proboscis extension response bioassay and preference experiments with free-flying bees. Naïve bees were indifferent to odors of avocado and citrus flowers and honey. Experienced bees, which were collected in the field during the blooming season, responded preferentially to odor of citrus flowers. The unique sugar composition of avocado nectar, which contains almost exclusively sucrose and a low concentration of the rare carbohydrate perseitol, and the dark brown color of avocado honey, had no negative effects on its attractiveness to the bees. Phenolic compounds extracted from avocado honey were attractive to bees and adding them to a solution of sucrose increased its attractiveness. Compared with citrus nectar and nonavocado honey, avocado nectar and honey were rich in a wide range of minerals, including potassium, phosphorus, magnesium, sulfur, iron, and copper. Potassium and phosphorus, the two major minerals, both had a repellent effect on the bees. Possible explanations for the presence of repellent components in avocado nectar are discussed.