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1.
《化学进展》2012,(1):5-7
田禾精细化工专家。华东理工大学教授。1962年7月出生于新疆乌鲁木齐,籍贯江苏常熟。1982年7月毕业于南京理工大学化学化工学院,1986年7月和1989年1月在华东理工大学先后获硕士学位和工学博士学位。现任国际学术刊物Dyes and Pigments主编。  相似文献   

2.
正《功能高分子学报》是国家教育部主管、华东理工大学主办的专业性学术刊物。其宗旨是反映我国功能高分子领域的科研成果,促进国内外学术交流,为加速实现我国社会主义现代化建设服务。刊登内容主要为功能高分子和其他高分子领域具有创新意义的学术论文。设论文、综述、简报、快报等栏目。竭诚欢迎本领域的专家、学者投稿。1投稿须知1.1来稿必须具有创新性、学术性、科学性和可读性。文题要确切、简练、醒目。署名作者应是对文稿做出贡献的人。1.2来稿切勿一稿多投。文稿自收到之日起,1个月内本刊决定是否录用。来稿一律不退,请自留底稿。1.3编辑部将按规范的程序,聘请有关专家评审,最后经编委会终审,公平、公正、慎重地决定稿件的取舍。录用稿件的发表周期为6-9个月。1.4本刊现为纸张印刷版一光盘版一网络版三位一体的出刊模式,凡本刊录用的稿件,将同  相似文献   

3.
临床上将高血压分为原发性和继发性两类。原发性高血压称为高血压病。高血压症分为3型,即缓进型、急进型和老年性高血压。老年性高血压又称收缩性高血压,其特征是收缩压升高,舒张压变化很小,脉压增大,常合并冠心病。高血压症与微量元素锶、锌、铜有关。国内研究发现,人体内锶(Sr)含量愈低,则血压愈高。一期、二期、三期高血压患者的锶含量分别为5·26×10-3、2·77×10-3和1·65×10-3。国外学者观察46例妊娠高血压患者,其锌、铜、硒、铁、钙、镁及维生素E缺乏。但也有报道指出,高血压患者头发铜及血清铜升高。作者认为,出现这两种截然不同的结果是可以理解的。情况可能无变化,缺锌易患高血压,但早期缺锌者其血铜可能无变化,因锌与铜相拮抗,长期或严重缺锌会导致血铜升高。高血压患者应补充钾、锶、锌和硒。有遗传性钠过敏史者,高钠摄入、高钠潴留是导致高血压的危险因素。钠、钾相拮抗,因此补钾可减少体内钠的潴留。水果和蔬菜是富钾食物。服用药物碘化钾或碘酸钾应有医师指导。海带中锶含量相当高,是理想的补锶食品。核桃、花生、芝麻和瘦肉富锌。服用硒锌氨基酸口服液既可补锌又能补硒,对改善临床症状效果明显。此外,减少患者体内的铅、镉负荷有利于...  相似文献   

4.
中国化学会第27届学术年会定于2010年6月20~23日在福建省厦门市举行。大会主题:创新型社会与化学的责任。会期4天,6月19日报到。会议由中国化学会主办,厦门大学承办,中国科学院福建物质结构研究所协办。  相似文献   

5.
呼吸道感染与微量元素   总被引:1,自引:0,他引:1  
急性上呼吸道感染是一种常见病,发病率高,传染性强,各年龄组均可发病。上呼吸道感染是鼻、咽、喉部炎症的总称。其中以普通感冒最为常见,多数由病毒引起,亦可为细菌所致。反复呼吸道感染是小儿常见病。扁桃腺炎发作后,可并发急性肾炎、风湿热等,应予高度重视,积极预防和治疗。呼吸道感染,特别是反复呼吸道感染多系机体免疫力低下所致。实验研究证实,微量元素锌、硒、铁、锰、铜缺乏及铅过高可使机体免疫力显著下降。临床观察到,反复呼吸道感染儿童头发锌值明显低于对照组;反复发生上呼吸道感染且低锌的儿童,其血清免疫球蛋白A和免疫球蛋白G也降低。分泌型免疫球蛋白A(IgA)在防御呼吸道感染中起主要作用。还有人观察到,反复呼吸道感染(RRTI)患儿的血清锌含量明显低于对载体也可以转运锶,血清锶含量增加可以竞争钙的载体,影响钙的吸收利用。支气管平滑肌细胞内的Ca2+含量是维持平滑肌纤维正常舒缩的基本条件。此外,Ca2+不仅参与支气管腺体分泌的控制,而且与肥大细胞释放生物介质密切相关。因此,支气管哮喘患者应补充钙元素借以维持血中Ca2+含量并减少体内锶的蓄积。如前所述,哮喘有外源性与内源性之分。内源性哮喘往往先有上呼吸道感染史。随感染的加重而迁...  相似文献   

6.
<正>2013年是我国著名无机化学家、中国科学院院士游效曾先生80华诞。游效曾先生,1934年生。武汉大学学士,南京大学硕士。美国威士康星、伊利诺伊和佛罗里达大学访问学者。被聘为西班牙Alcala大学、香港大学、新加坡国立大学和台湾大学客座教授。1991年当选中国科学院院士。游效曾教授先后任南京大学配位化学研究所所长,国家重点实验室和化学化工学院学术  相似文献   

7.
2011年11月29日,我们敬爱的导师张滂院士与世长辞。噩耗传来,作为学生的我们悲痛万分。师恩难忘,谨以此文作为对先生的纪念,并表达我们对先生的感谢与怀念之情。张滂先生早年就读于西南联大,毕业后曾作为老一辈有机化学家吴学周先生的助手开展研究工作。1945年留学英国,先后就读于利兹大学和剑桥大学,1949年7月获得有机化学博士学位。据了解,张滂先生是第一位获得剑桥大学博士学位的中国人。张先生于新中国成立之际回国效力,投身于祖国的教育和科技事业,先后任教于燕京大学和北京大学。  相似文献   

8.
<正>一、投稿要求1.稿件内容须符合本刊的报导宗旨,论点鲜明,数据可靠,文字简练。来稿文责自负。2.接受网上投稿。投稿信箱:gzhx@gic.ac.cn3.来稿一经刊出,酌付稿酬,并赠送当期杂志。  相似文献   

9.
实验1氨基酸的离子交换色谱离子交换色谱是分离和制备带电物质的重要方法。其原理是基于被分离物的电荷与树脂上的相反电荷的相互作用。本实验内容是分离一个含3种氨基酸的混合物。然后根据特定的显色反应,定量测定从色谱柱上洗脱的每种氨基酸。3种氨基酸(结构如下)以混合物的形式提供给选手。它们是组氨酸(His)、胱氨酸(Cys)、和精氨酸(Arg)。3种氨基酸(结构如下)以混合物的形式提供给选手。它们是组氨酸(His)、胱氨酸(Cys)、和精氨酸(Arg)。离子交换树脂是胶联的磺化聚苯乙烯(柱层析装置见下图)。在实验开始前,离子交换柱已用洗脱剂1平…  相似文献   

10.
离子色谱-直接电导法测定碱土金属和过渡金属离子   总被引:1,自引:0,他引:1  
本文报道离子色谱-直接电导法测定碱土金属和过渡金属离子。研究了流动相pH值、乙二胺浓度及柠檬酸和酒石酸浓度对金属离子分离的影响。结果表明,以乙二胺-柠檬酸为流动相可以同时分离碱土金属和过渡金属离子。用乙二胺-酒石酸作为流动相可以分离碱土金属离子。方法检出限为0.09~1.88 mg/L,加标回收率为97.6%~98.7%。该方法用于叶面肥试样的分析,结果良好。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

13.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

14.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

15.
16.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

17.
Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.  相似文献   

18.
A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.  相似文献   

19.
A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).  相似文献   

20.
Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO4 oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.  相似文献   

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