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1.
鞠洪振 《中国橡胶》2004,20(13):3-7
改革开放以来,我国橡胶工业的发展速度是前所未有的,其间有许多成功的经验,特别是入世后,在上世纪末全行业整体亏损的不利情况下,大家认识一致,认真对待,风雨同舟,趋利避害,经受住了考验,不仅行业经济全面复苏,而且取得新的发展。当前,全行业面对的是新一轮的竞争,而且更为激烈  相似文献   

2.
《中华手工》2011,(12):60-61
两期"台湾工艺之旅"圆满结束。对于文化艺术,无论是走马观花还是深度阅读,各人经历不同感悟也会不一样。你心目中的台湾,是什么样子呢?8天的旅程,累,却幸福着。忘不了,太鲁阁天然大理石岩的鬼斧神工,忘不了,清晨日月潭散发的柔美光辉,忘不了,黄安福大师表演玻璃技艺洒下的滴滴汗珠,忘不了,粘碧华大师的艺术之家和她亲切的笑容,忘不了,汉声巷黄永松老师挥手作别时眼里的殷殷期盼,忘不了,台北世界设计展上将书法创意延伸的"妙法自然"忘不了,中华手工电台带给我们的欢声和笑语,忘不了……黄永松老师说,这一代人需要觉醒,但觉醒的方向不要错,要回到文化的母土。或许你已留意到,  相似文献   

3.
柳林小径深处,一扇木门掩映的白色建筑,即是王功新林天苗夫妇在宋庄的别墅。从大门进来,前方是白色的月亮门,像一道影壁墙,遮蔽外人的视线,经过一片水竹摇曳的甬道,才入院子。院内,三层小楼房顶上两层主体分别向两侧挑空,蜿蜒的池塘从花园延伸至室内,隔着一面大大的落地玻璃墙,恍惚间分不清哪里是室内,哪里是室外。更不可思议的是,池塘中间竟然是空的,下面就是那个巨大的工作室,鱼儿游过,涟漪荡漾开来,总担心这水会不会溢出……  相似文献   

4.
捕鸟蛛     
《中华手工》2013,(10):33+91
凶悍的捕鸟蛛,已经抓住一只小鸟,正分泌毒液将猎物毒死,刚孵化的小鸟心有不甘,瞪大眼睛,却对身体的麻痹无可奈何,捕鸟蛛得意洋洋,八只毛茸茸的爪子渐渐放松,似乎要开始安心享用猎物。凶狠的捕杀场面,被作者处理得惟妙惟肖,全身长毛的蜘蛛、绝望的小鸟,让观者毛骨悚然。那么,请您猜猜看,这幅捕鸟蛛猎杀图,是用什么材质做成的呢?  相似文献   

5.
陈婷 《粘接》2012,(10):19-19
秋至过后,几场不经意的细雨飘来,将炎热一点点打退,正如人们所言"一场秋雨一场凉"。如果说春天把嫩绿给了三月,夏天把翠绿给了七月,冬天把洁白给了十二月,那么秋天,就把金色给了十月。十月,是花开飘香的季节。菊花开了,红的、黄的、白的,朵朵怒放着,风情万种、婀娜多姿;桂花开了,偶尔外出,惊奇的发现满枝的桂花把树木装扮的耀眼夺目,一阵微风吹过,阵阵清新淡雅香气飘来,沁人心脾。工作一天的烦躁情绪,在这别样的景象下瞬间被一扫而光。  相似文献   

6.
尾矿干式堆存在磷矿山选矿厂中的应用   总被引:1,自引:0,他引:1  
0 引言 尾矿设施具有保护环境,充分利用水资源和保护矿产资源的作用,是矿山生产不可缺少的设施,但投资巨大,基建投资占矿山总投资的10%以上,占选矿厂投资的20%左右,有的几乎与选矿厂的投资一样多,甚至超过选矿厂.尾矿设施的运行成本也较高,有些矿山尾矿设施运行成本占选矿厂生产成本的30%以上.近年来,由于征购土地和搬迁农户的费用越来越高,因此建设尾矿设施的费用也越来越高.此外,尾矿库还是矿山生产的最大的危险源之一,一旦尾矿库失事,将给工农业生产及下游人民生命财产造成巨大损失.而若采用干式堆存尾矿,则可较大地缓解以上矛盾,因干式堆存的尾矿只含有11%~15%的水分,且可依地形而堆存,大大减少了占地面积,且不易垮落.贵州某一选矿厂利用脱水设备实现了尾矿的干式堆存,情况介绍如下.  相似文献   

7.
走在路上     
《聚氨酯》2013,(11):4-4
<正>冬至已过,最近天气渐渐凉了,下班的路上每天必须走过一座高架桥,沿着楼梯爬上去,冷风吹过来,瞬间清醒,连一整天工作的疲惫也消失的无影无踪了。搬家过去的前几天,上下班从高架桥上爬上爬下,左手拎着饭盒,右手拎着刚从菜市场买的菜,炎热的盛夏令人无比烦躁,心想明明直线距离很短的,走个高架桥就绕好多路,可偏偏也没别的小道走,于是每天就当做锻炼身体,慢慢适应了上下班的节奏。  相似文献   

8.
罗维钧 《江西化工》2007,(2):120-121
管理是一门科学,更是一门艺术,班级足学校最基本单位.从某种意义上讲,班级管理工作的好坏,直接反映了一个学校的管理水平,如何使班级管理的科学性艺术性有机地统一起来,是我们每一位教师尤其是班主任老师值得深思的重大课题.我们必须清楚地认识到学生是班级的主体,班级管理必须认他们为中心来展开,民主化,科学化,人性化的班级管理是促进学生团结,锻炼学生能力,融洽师生关系的重要前提.只有这样,我们才能更好地促进学生全面发展,才能说是对学生、家长及社会负责,下面我就班级管理的民主化,科学化,人性化方面谈谈自己的一些看法与认识.  相似文献   

9.
在我国陶瓷美术发展史上,凡有所成就,有所作为的陶瓷美术家,不论哪个时代,哪个艺术院派,都离不开继承传统,吸取精华,并通过自己的长期实践,不断创新,才形成自己独有的艺术风格.景德镇陶瓷美术家王步先生创作的青花作品,以其笔简意骇,博大精深,水色莹澈,淋漓尽致的风格,为人们所称赞.本文试就他的艺术风格归纳为三个方面来简略论述.  相似文献   

10.
小鱼 《中华手工》2013,(10):78-79
正入花甲之年的葛新华,20年默默收藏3000多把老算盘,为的是让人们在被键盘和鼠标声占满的今天,还能记得算珠拨动的旋律。"打主意,秋千格。"打一物品是什么?在没有计算器和电脑的年岁,这个几乎存在每家每户的老物件,如今已经慢慢淡出了人们的视野。曾几何时,珠算课是小学里必修的课程,儿时背着算盘上学堂,算珠在背后摇得"噼里啪啦"响;账房里的老先生记账算数,加减乘除,样样离不开打算盘。然而,当算盘逐渐远去时,有一个人,仍然守护着算盘拨动的记忆,经历长长20个年头,默默收集3000多把老算盘,他最欣慰的,是成立了自己独具特色的家庭式收藏馆,他就是葛新华。这位热爱算盘如痴,喜爱"精打细算"的老者年纪60岁,在他的收藏馆里,可以看到琳琅满目的算盘世界。墙上歪歪斜斜不规则地挂着许多算盘,  相似文献   

11.
The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.  相似文献   

12.
Abiotic stresses, such as drought, salinity, heat, cold, and heavy metals, are associated with global climate change and hamper plant growth and development, affecting crop yields and quality. However, the negative effects of abiotic stresses can be mitigated through exogenous treatments using small biomolecules. For example, the foliar application of melatonin provides the following: it protects the photosynthetic apparatus; it increases the antioxidant defenses, osmoprotectant, and soluble sugar levels; it prevents tissue damage and reduces electrolyte leakage; it improves reactive oxygen species (ROS) scavenging; and it increases biomass, maintains the redox and ion homeostasis, and improves gaseous exchange. Glutathione spray upregulates the glyoxalase system, reduces methylglyoxal (MG) toxicity and oxidative stress, decreases hydrogen peroxide and malondialdehyde accumulation, improves the defense mechanisms, tissue repairs, and nitrogen fixation, and upregulates the phytochelatins. The exogenous application of proline enhances growth and other physiological characteristics, upregulates osmoprotection, protects the integrity of the plasma lemma, reduces lipid peroxidation, increases photosynthetic pigments, phenolic acids, flavonoids, and amino acids, and enhances stress tolerance, carbon fixation, and leaf nitrogen content. The foliar application of glycine betaine improves growth, upregulates osmoprotection and osmoregulation, increases relative water content, net photosynthetic rate, and catalase activity, decreases photorespiration, ion leakage, and lipid peroxidation, protects the oxygen-evolving complex, and prevents chlorosis. Chemical priming has various important advantages over transgenic technology as it is typically more affordable for farmers and safe for plants, people, and animals, while being considered environmentally acceptable. Chemical priming helps to improve the quality and quantity of the yield. This review summarizes and discusses how exogenous melatonin, glutathione, proline, and glycine betaine can help crops combat abiotic stresses.  相似文献   

13.
Anaphylaxis is a severe, acute, life-threatening multisystem allergic reaction resulting from the release of a plethora of mediators from mast cells culminating in serious respiratory, cardiovascular and mucocutaneous manifestations that can be fatal. Medications, foods, latex, exercise, hormones (progesterone), and clonal mast cell disorders may be responsible. More recently, novel syndromes such as delayed reactions to red meat and hereditary alpha tryptasemia have been described. Anaphylaxis manifests as sudden onset urticaria, pruritus, flushing, erythema, angioedema (lips, tongue, airways, periphery), myocardial dysfunction (hypovolemia, distributive or mixed shock and arrhythmias), rhinitis, wheezing and stridor. Vomiting, diarrhea, scrotal edema, uterine cramps, vaginal bleeding, urinary incontinence, dizziness, seizures, confusion, and syncope may occur. The traditional (or classical) pathway is mediated via T cells, Th2 cytokines (such as IL-4 and 5), B cell production of IgE and subsequent crosslinking of the high affinity IgE receptor (FcεRI) on mast cells and basophils by IgE-antigen complexes, culminating in mast cell and basophil degranulation. Degranulation results in the release of preformed mediators (histamine, heparin, tryptase, chymase, carboxypeptidase, cathepsin G and tumor necrosis factor alpha (TNF-α), and of de novo synthesized ones such as lipid mediators (cysteinyl leukotrienes), platelet activating factor (PAF), cytokines and growth factors such as vascular endothelial growth factor (VEGF). Of these, histamine, tryptase, cathepsin G, TNF-α, LTC4, PAF and VEGF can increase vascular permeability. Recent data suggest that mast cell-derived histamine and PAF can activate nitric oxide production from endothelium and set into motion a signaling cascade that leads to dilatation of blood vessels and dysfunction of the endothelial barrier. The latter, characterized by the opening of adherens junctions, leads to increased capillary permeability and fluid extravasation. These changes contribute to airway edema, hypovolemia, and distributive shock, with potentially fatal consequences. In this review, besides mechanisms (endotypes) underlying IgE-mediated anaphylaxis, we also provide a brief overview of IgG-, complement-, contact system-, cytokine- and mast cell-mediated reactions that can result in phenotypes resembling IgE-mediated anaphylaxis. Such classifications can lead the way to precision medicine approaches to the management of this complex disease.  相似文献   

14.
以中低温煤焦油轻油和重油为实验原料,采用常压蒸馏获得170~200℃、200~240℃、240~270℃、270~300℃、300~320℃、320~340℃、340~360℃和360~390℃煤焦油馏分油;利用配有油品加氧制冷进样系统的ICP-OES测定了21种微量元素在馏分油中的含量,考察了不同馏分油中元素的分布情况。研究表明:在原煤焦油中,未发现Ag、Mg、Mo、Na、Ni、Fe、Mn、Cr及Ti元素,含量较高的元素有Sn、P、Al、Pb、Si,其中Sn元素在轻油和重油中的含量分别为11.78μg/g和14.04μg/g;在所有馏分油中,未发现Al、Mo、Fe、Mn、Cr及Ti元素,含量比较高的元素有Si、Sn、Na、Zn、Pb,特别是Si、Na、Sn、Zn、Ni、Pb及B元素可以有效富集于馏分油中。可能的原因是Ca、Fe、Mg、Al等金属以不同的盐类形态存在,在煤焦油脱水及<170℃蒸馏过程中,这些金属盐类会被部分带出,导致其在馏分油中的含量未富集或未检出;通过关联金属元素在馏分油中的分布与其组成的关系,馏分油中元素的分布可能与酚类化合物、杂环化合物和蒸馏温度等相关。酚类化合物及杂环化合物可能与Ag、B、Cu、Mo、Sn、Na、Zn、Ca、Pb等金属形成络合物或卟啉配合物,蒸馏温度一方面可以破坏Sn、Cd、Pb、Zn、Cu、Ca、Pb等元素在馏分油中的结合力,另一方面也可以促进这些元素与馏分油中的含氧、含氮等化合物更好地发生化合反应,进而影响金属元素在馏分油中的含量分布。  相似文献   

15.
16.
This article summarizes and reviews the various preparation methods, physical properties, and potential applications of one-dimensional nanostructures of conjugated polyaniline (PANI), polypyrrole (PPY) and poly(3,4-ethylenedioxythiophene) (PEDOT). The synthesis approaches include hard physical template method, soft chemical template method, electrospinning, and lithography techniques. Particularly, the electronic transport (e.g., electrical conductivity, current-voltage (I-V) characteristics, magnetoresistance, and nanocontact resistance) and mechanical properties of individual nanowires/tubes, and specific heat capacity, magnetic susceptibility, and optical properties of the polymer nanostructures are presented with emphasis on size-dependent behaviors. Several potential applications and corresponding challenges of these nanofibers and nanotubes in chemical, optical and bio-sensors, nano-diodes, field effect transistors, field emission and electrochromic displays, super-capacitors and energy storage, actuators, drug delivery, neural interfaces, and protein purification are also discussed.  相似文献   

17.
松香是一类产量丰富、价格低廉的可再生林产资源,被广泛地应用于食品、农业、橡胶、油墨、涂料等领域。松香的三环二萜结构具有超强的疏水性,通过催化异构、Diels-Alder加成等手段引入亲水基团可制备高附加值、易生物降解的绿色表面活性剂。本文从阴离子、阳离子、非离子和两性离子表面活性剂4个大类对松香基表面活性剂应用的文献及专利进行综述,重点分析了羧酸盐、磺酸盐、硫酸盐和磷酸盐4种阴离子型表面活性剂和季铵盐阳离子型表面活性剂,多元醇型和聚氧乙烯型非离子表面活性剂,以及甜菜碱型和氧化胺型两性离子表面活性剂。剖析松香基表面活性剂产业化开发的新技术及新产品概况,提出松香基表面活性剂替代传统表面活性剂的潜在应用领域。同时,对松香基表面活性剂的研究发展与产业化发展进行了评价与展望。  相似文献   

18.
Separation and purification techniques are applied in many important fields, such as in the medical, chemical, metallurgical, environmental, and pharmaceutical industries. Recent advances in separation science and the urgent need for highly selective purification have necessitated a rapid progress with respect to the reagents, chemicals, and surfactants used in separation processes to attain a high efficiency and selectivity. Polymeric materials have attracted considerable interest, and they have been widely used as extractants, catalysts, and modifiers, in separation and purification processes. This review outlines the recent advances in the use of novel polymers, natural and synthetic, in different separation and purification techniques. Various separation techniques such as chromatography, crystallization, precipitation, distillation, electrophoresis, filtration, and mineral processing methods are discussed, and the polymers used in each method are described in terms of their properties, structure, and function. The application of polymers shows great promise in achieving a highly efficient separation, especially in the areas of membrane separation and water purification. The rational design of new multifunctional polymers with triggered functions presumably presents new opportunities for the development of advanced separation methods.  相似文献   

19.
Shifeng Dai  Dexin Han 《Fuel》2006,85(4):456-464
Coals from Luquan, Yunnan Province, China, have high contents of cutinite and microsporinite, with an average of 55 and 33.5 vol%, respectively, (on a mineral-free basis). The coals are classified as cutinitic liptobiolith, sporinite-rich durain, cutinite-rich durain, and sporinitic liptobiolith. These four liptinite-rich coals are often interlayered within the coal bed section and vary transversely within the coal bed. The vitrinite content varies from as low as 1.6-20.5% (mineral-free basis), and it is dominated by collodetrinite, collotelinite, and corpogelinite. The maceral composition may be attributed to the type of the peat-forming plant communities. Moreover, the Luquan coals are characterized by high contents of volatile matter, hydrogen, and oxygen, and the high values of the atomic hydrogen to carbon ratio as a result of the maceral composition. As compared with the common Chinese coals and the upper continental crust, the Luquan coals are enriched in Li, B, Cu, Ga, Se, Rb, Mo, Ba, Pb, Bi, and U, with averages of 99.9, 250, 111, 24.4, 4.55, 130, 58.8, 1276, 162, 3.85, and 34.1 μg/g, respectively. The SEM-EDX results show that V, Cr, Ga, and Rb occur mainly in clay minerals, and Cu and Pb are associated with clay minerals and pyrite, and Mo and U are mainly in clay minerals and organic matter. Barite and clay minerals are the main carrier of barium. The high B and U contents are probably resulted from deep seawater influence during coal formation.  相似文献   

20.
Laccases (Lac) and tyrosinases (TYR) are mild oxidants with a great potential in research and industry. In this work, we review recent advances in their use in organic synthesis. We summarize recent examples of Lac-catalyzed oxidation, homocoupling and heterocoupling, and TYR-catalyzed ortho-hydroxylation of phenols. We highlight the combination of Lac and TYR with other enzymes or chemical catalysts. We also point out the biological and pharmaceutical potential of the products, such as dimers of piceid, lignols, isorhamnetin, rutin, caffeic acid, 4-hydroxychalcones, thiols, hybrid antibiotics, benzimidazoles, benzothiazoles, pyrimidine derivatives, hydroxytyrosols, alkylcatechols, halocatechols, or dihydrocaffeoyl esters, etc. These products include radical scavengers; antibacterial, antiviral, and antitumor compounds; and building blocks for bioactive compounds and drugs. We summarize the available enzyme sources and discuss the scalability of their use in organic synthesis. In conclusion, we assume that the intensive use of laccases and tyrosinases in organic synthesis will yield new bioactive compounds and, in the long-term, reduce the environmental impact of industrial organic chemistry.  相似文献   

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