丙烷脒杀菌剂的研究进展

丙烷脒是一种新型杀菌剂。主要阐述了丙烷脒的合成方法、杀菌作用、应用优势、现状和发展前景。     

丙烷脒杀菌剂的研究进展

丙烷脒是一种新型杀菌剂。本文主要阐述了丙烷脒的合成方法、杀菌作用、应用优势、现状和发展前景。     

对硝基苯甲腈的脒基化反应的合成研究

<正>对硝基苯甲脒是一种重要的化工中间体原料,在医药、染料、农药等方面有着广泛的应用,但关于它的合成少见报道。对硝基苯甲脒可以做丙烷脒药物中间体,用于防治灰霉病病菌。国内杨凌农药化工有限公司与美国NZYM公司合作开发出了2%丙烷脒水剂,其化学名称为1,3-二(4-脒基苯氧基)丙烷。丙烷脒对灰霉病病菌防效高,用量低,单位面积的有效成分投入量小,对环境的化学污染程度     

合成的烷基脒类杀菌剂在杨凌中试成功

属国内首家合成，具有自主知识产权的烷基脒类杀菌剂在杨凌试验成功。其产品丙烷脒对作物灰霉病防效高，用量少，成本低，使用安全，具内吸杀菌活性，并对作物生长有一定的刺激作用，是一种全新的无公害杀菌剂。[第一段]     

新型安全环保杀菌剂——丙烷脒

丙烷脒属烷基脒类化合物,该类物质在医药上早有应用和研究.在一次偶然事件中,美国NZYM公司发现了该类化合物中的戊烷脒对草莓灰霉病菌(Botrytis cirerea)的抑菌活性,并通过一系列的室内试验,戊烷脒的抑菌活性得到了确证.自1999年起,西北农林科技大学无公害农药研究服务中心(以下简称"中心")与NZYM公司合作,开始致力于将该类化合物开发成为农用杀菌剂的研究.     

我国自主开发农药的专利情况

国内近年来开发了一些新的农药品种,其中一些申请了中国专利,甚至国外专利。一些已查明专利情况的国内开发品种如下: 1.除草剂品种6个:单嘧磺隆、双甲胺草磷、SYP-249、SYP-298、丙酯草醚、异丙酯草醚。此6个品种均处于专利有效期内。 2.杀虫剂品种11个:苦皮藤素、雷公藤甲素、溴灭菊酯、氟螨、溴氟菊酯、蛇床子素、丙烷脒、硫肟醚、呋喃虫酰肼、硝虫硫磷和右旋氯丙炔菊酯。苦皮藤素、雷公藤甲素、溴灭菊酯和氟螨未申请专利。溴氟菊酯专利权已终止。蛇床子素部分无效。丙烷脒处于专利审查过程中。右旋氯丙炔菊酯、硫肟醚、呋喃虫酰肼和硝虫硫磷处于专利有效期。     

新型杀菌剂丙烷脒经济高效

西北农林科技大学无公害农药研究服务中心开发成功的"新型杀菌剂丙烷脒"获得两项国家发明专利。该产品对作物灰霉病防效高,用量少,成本低,使用安全,具内吸杀菌活性,并对作物生长有一定的刺激作用,是一种全新的无公害杀菌剂。     

丙烷脒类似物抑菌活性研究

以番茄灰霉病菌和白菜黑斑病菌等植物病原菌作为供试生物,用抑制菌丝生长速率法测定了合成的10个丙烷脒类似物的抑菌活性。结果表明：在供试浓度为10mg／L时,化合物A1-A5对番茄灰霉病菌、白菜黑斑病菌、苹果干腐病菌和烟草赤星病菌菌丝生长抑制率均在80％以上;化合物B5对小麦纹枯病菌菌丝生长抑制率为82．2％,值得进一步研究。     

高聚合度聚乙烯醇的制备

采用醋酸乙烯酯为单体,以OP-10和十二烷基硫酸钠为复配乳化剂,偶氮二脒基丙烷盐酸盐为引发剂,通过正交实验研究了乳液聚合法制备高聚合度聚醋酸乙烯酯的最佳工艺条件.通过单因素实验验证了最佳工艺条件的可靠性,并分析了乳化剂用量、引发剂用量和反应温度对醋酸乙烯酯平均聚合度的影响规律.在最佳工艺条件下制得了聚合度为5 100的聚醋酸乙烯酯,经醇解得到了聚合度为4 800的聚乙烯醇.     

脒类化合物合成方法的研究进展

脒类化合物一般用作消炎药、抗菌素、泌尿及心血管疾病用药,另外一些种类的脒类化合物具有较好的抗癌活性。脒类化合物作为杀螨杀虫剂,具有广谱、低毒、活性高的优势。脒类化合物的传统合成方法以酰胺法、腈的氨解法和原甲酸酯法为主。而现在脒类化合物方面的研究方向主要在缩合剂和催化剂方面,以提高脒类化合物的产率。笔者总结了脒类化合物的各种合成方式,并提出了脒类化合物生产开发的合理化建议。     

Mechanisms Governing Anaphylaxis: Inflammatory Cells,Mediators, Endothelial Gap Junctions and Beyond

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.     

微波消解-石墨炉原子吸收法测定唇膏中4种金属的含量

唇膏经微波消解,石墨炉原子吸收光谱法测定样品中铅、锰、铬、镉的含量。在优化的仪器工作条件下,质量浓度分别在32.0、8.0、8.0、8.0 mg/L范围内呈良好的线性关系,检出限分别为4.2、3.5、2.3、2.5μg/L,测得回收率在98%~103%之间,精密度分别为4.1%、3.6%、3.9%、2.7%。     

Hydrocarbon components of the yellowheaded spruce sawfly sex pheromone

The primary sex pheromone of the yellowheaded spruce sawfly,Pikonema alaskensis (Rohwer) (Hymenoptera: Tenthredinidae), was found to include a series of straight-chain hydrocarbon dienes, all with the double bonds in the 9 and 19 positions and all with the (Z, Z) configuration. The major components, of 29, 31, 33, 35, and 37 carbon atoms, were synthesized. In the field and the greenhouse, the synthetic dienes were far above control levels in activity but, at least during the first hours of bioassay, were somewhat less active than the female-derived materials on a weight basis. In the field, a mixture of all five synthetic dienes, in the proportions found in the females, was more attractive than any single one, on a mole basis. In addition, (Z, Z)-9,19 dienes of 28, 30, 32, 34, 36, 38, and 39 carbons have been detected in females in minor amounts. The first five were bioassayed, and each was found to be similar in activity to the 35-carbon component when compared on a weight basis. The synthetic dienes, while active by themselves, were strongly synergized by two, more polar, Florisil fractions derived from females. Experimental design considerations are discussed.     

Field evidence of synergism and inhibition in the sesiidae sex pheromone system

The E,Z, Z,Z, and Z,E geometric isomers of 3,13 octadecadien-1-ol acetate were used singly and in binary combinations to trap sesiids in Wisconsin cherry orchards. The Z,E isomer alone did not capture any sesiids. A synergistic effect, however, of Z,E onSynanthedon pictipes response to its pheromone E,Z was demonstrated for the first time. Strong inhibitory effects of the Z,Z isomer onS. pictipes response to E,Z, and of the E,Z isomer onS. scitula response to Z,Z, were found. As little as 0.5% of Z,Z in E,Z completely inhibited theS. pictipes response. This species' response was also reduced by 85% when Z,Z was evaporated at 4 points, each ca. 6 m from the pheromone trap. Consistencies and discrepancies of the data with relevant experimental results from other geographical areas are briefly discussed.Lepidoptera: Sesiidae (=Aegeriidae), the clearwing moths.Research supported by the College of Agriculture and Life Sciences, University of Wisconsin, Madison, and by the Wisconsin Red Tart Cherry Ind. Market. Order.     

Soil nutrient depletion by agricultural production in Southern Mali

The degree of soil mining by agricultural production in Southern Mali is assessed by calculating nutrient balances: differences between the amount of plant nutrients exported from the cultivated fields, and those added to the fields. Export processes include extraction by crops, losses due to leaching, to erosion, and to volatilization and denitrification. Inputs include applications of fertilizer and manure, restitution of crop residues, nitrogen fixation, atmospheric deposition of nutrients in rain and dust, and enrichment by weathering of soil minerals. Nutrient balances are calculated for N, P, K, Ca, and Mg. Both pessimistic and optimistic estimates are given.The resulting figures indicate, even when the most optimistic estimates are used, large deficits for nitrogen, potassium and magnesium. For the region as a whole, the calculated deficits are -25 kg N/ha,-20 kg K/ha, and -5 kg Mg/ha. Further, acidification is to be expected, in particular in areas where cotton is grown. The deficits are caused by traditional cereal crops, but also by cotton and especially by groundnut. The latter two crops are fertilized, but insufficiently. It is important to note, that the negative figures are not automatic recommendations for application of a specific amount of additional fertilizer. For phosphorus and calcium the balance of the region as a whole appears to be about in equilibrium, but locally large variations may occur.Erosion and denitrification are important causes of nutrient loss, accounting respectively for 17 and 22% of total nitrogen exports. Atmospheric deposition and weathering of minerals in the soil are still important nutrient inputs that contribute as much as nutrients as organic and mineral fertilizer combined. Nutrient depletion is very large in comparison to the amount of fertilizer applied. Drastic options, such as doubling the application of fertilizer or manure, or halving erosion losses, even if feasible, would still not be enough to make up for the calculated deficits.The annual value of withdrawn nutrients, if related to prices of fertilizers, varies between 10,000 and 15,000 FCFA/ha (40-60 US $/ha). Since the estimated average gross margin from farming in this area is 34,000 FCFA/ha (123 US $/ha), soil mining appears to provide an amount equal to 40% of farmers' total income from agricultural activities.     

陶瓷名物探源二则

匋、陶、窑(窯)上古皆读成舌头音,意义又相通,实际为一个意义上先后产生的几个形体不同的字,先民以陶(匋)既称呼窑灶,又指窑灶出品之物,又指制作陶器;坏(坯)、瓶、瓬、瓿、甂、缶、钵、皿、杯(盃)、盆(瓫)均指窑灶所出之物或后世模仿窑灶出品之物,其字皆由重唇音演变而来,亦为同胞兄弟的同源词。     

典型过程强化技术在纳米材料制备中的应用进展

纳米材料被誉为21世纪的新材料,广泛应用于化工、电子、国防、陶瓷等领域.传统的纳米材料制备方法面临粒径控制较困难、批次间重复性差,存在放大效应等不足.过程强化技术是化学工程学科的研究前沿和热点方向之一,旨在通过在生产过程中采用新工艺、新设备等手段,实现缩减操作单元、减小设备体积、提高生产能力及能量利用效率的目的,是实现...     

明胶分子量分布测定和表征的研究进展(二)

<正> 6.SDS—PAGE(十二烷基硫酸钠-聚丙烯 酰胺凝胶电泳)法 从1959年Raymond和1964年Davis用聚丙烯酰胺凝胶分离人血清蛋白成功后,聚丙烯酰胺凝胶电泳得到了广泛的发展,成为分离、分析蛋白质、核酸类生物     

国内乙醛酸衍生产品的现状与展望(一)

本文结合国外情况对尿囊素、香兰素、乙基香兰素、对甲氧基苯甲醛、儿茶醛、胡椒醛、扁桃酸、二苯基乙酸、对羟基苯乙酸、苯并二呋喃酮系列化合物、苯甘氨酸、对羟基苯甘氨酸、泛酸钙、2-羟基喹(?)啉、2-羟基膦酰基乙酸等乙醛酸下游产品的国内市场与科研情况做了较详细地论述。预计,我国目前GA的总需求量约为9000t/a,消费构成大致为,苯甘氨酸类占42.3％、尿囊素占31.6％、芳香醛占20％、其它占6.1％,进口量约3000～4000t/a。     

Polymer and modified chitosan-based nanocomposite: impending material for technical application

This article highlights research endeavors on various aspects of polymer/modified chitosan nanocomposite counting their fabrication, features, application, and future prospects. Chitosan is biocompatible/biodegradable polymer having exclusive physical and chemical properties in modified forms. Chitosan possess enormous structural prospects through functionalization with carbon nanotube, graphene, nanoclay, and metal nanoparticle. Modified chitosan own optimal moisture absorption, heat stability, chemical and flame resistance. Incorporation of nano-functionalized chitosan in matrices generate innovative efficacies of nanocomposite in sensors, dye removal, membrane technology, packaging, antimicrobial, and biomedical materials. Polymer/modified chitosan nanocomposite reveal superior characteristics such as strength, heat stability, electrical conductivity, photo-luminescent, antimicrobial, and biomedical features.