泡沫塑料对贵金属—碘化亚锡—络合物的吸附分离行为研究

本文通过泡沫塑料对贵金属－碘化亚锡体系富集分离的条件，怀能和朵理的研究，建立了一种泡沫塑料同时富集分离微量铂，钯，铑，铱，金的新体系。实验结果表明，在１．０ｍｏｌ／ＬＨＣｌ，０．６ｍｏｌ／ＬＫＩ和０．０１ｍｏｌ／ＬＳｎＣｌ２的溶液中，振荡吸附３０ｍｉｎ。各元素分配系数均在１０＾５以上，吸附容量（ｍｍｏｌ／ｇ）分别为：铂０．２５，钯０．２４，铑０．１２，铱０．１０，金０．５２，回收率分别为：铂９９．     

甲基膦酸二甲庚酯萃取色谱法分离金,铂的研究

本文研究了以４．０ｍｏｌ．Ｌ Ｈ２ＳＯ４－０．５０ｍｏｌ／Ｌ ＭｇＳＯ４为流动相，以硅烷化硅球负载的甲基膦酸二甲庚酯作固定相，萃取色谱法使微量铂，金与常见贱金属分离，富集在色谱柱上的铂和金分别用０．１０ｍｏｌ／Ｌ ＨＣｌ和１．０％Ｎａ２ＳＯ３溶液洗脱进行连续分离与测定。经实际样品的试用考核，结果令人满意。     

贵金属同时浮选分离富集行为的研究及ICP－AES的测定

本文通过对贵金属－碘化钾－孔雀绿显色体系的浮选行为研究，建立了一种同时浮选富集分离铂、钯、铑、铱、金的新方法。实验结果表明，在０．３６ｍｏｌ／ＬＨＣｌ０．１ｍｏｌ／ＬＫＩ和２．４×１０￣（－４）ｍｏｌ／ＬＭＧ的溶液中，加入环已烷振荡１ｍｉｎ，铂、钯、铑、铱、金可被定量浮选，继而用ＩＣＰ－ＡＥＳ测定。对含量为５～１５０μｇ的贵金属，浮选回收率分别为铂８８．６％～９５．７％，钯９２．３％～９９．５％，铑９３．７％～１０１％，铱９２％～９８．５％，金８６．４％～９４％。方法应用于铜镍矿、铂网废料等物料中上述贵金属元素的测定，结果满意。     

流动注射—氢化物发生—非色散原子荧光光谱法直接测定海水中的砷（Ⅲ）和砷（

用流动注射－氢化物发生－非色散原子荧光光谱法对海水中Ａｓ（Ⅲ）和Ａｓ（Ⅴ）的直接测定进行了研究,氢化物发生的最佳条件为：ＫＨＢ４溶液浓度为５ｇ．Ｌ＾－１（含ＫＯＨ５ｇ．Ｌ＾－１）,流速１０．０ｍＬ．ｍｉｎ＾－１;样品酸度为１．３ｍｏｌ．Ｌ＾－１ＨＣｌ,流速４．２ｍＬ．ｍｉｎ＾－１。对基体ＮａＣｌ,ＭｇＣｌ２,ＣａＣｌ２,Ｎａ２ＳＯ４以及微量共存金属离子（Ｃｄ,Ｚｎ,Ｐｄ,Ｃｕ）的干扰实验结果表明,基体和微量共存金属离子对Ａｓ（Ⅲ）的测定没有干扰。样品中Ａｓ（Ⅴ）的测定用硫脲进行预还原,通过总量和Ａｓ（Ⅲ）的含量的差减得到Ａｓ（Ⅴ）含量,在优化实验条件下下测量方法的检出限（３σ）为０．０８ｎｇ．ｍＬ＾－１;７次测定的相对标准偏差为０．４８％－１．３０％（８．０ｎｇ．ｍＬ＾－１标准溶液）。标准曲线和标准加入法对海水     

在线流动注射螯合树脂预富集石英缝管增敏火焰原子吸收法测定水中痕量铅

应用高效的在线流动注射螯合树脂预富集石英缝管增敏火焰原子吸收系统直接测定水呈痕量铅。实验用内装２００ｍｇＡｍｂｅｒｌｉｔｅＸＡＤ－４键合的５－磺酸－８羟基喹啉螯合树脂的锥形柱,在ＰＨ９条件下样品流速为８．０ｍＬ／ｍｉｎ,９０ｓ采样,用０．５ｍｏｌ／Ｌ Ｈｃｌ洗脱,在分析速度为３０样／ｈ,获得３６倍的富集,经石英缝管增敏,灵敏度提高达１１５倍,线性范围为０－２００μｇ／Ｌ,检出限为１μｇ／Ｌ。铅含量水平５０μｇ／Ｌ的水样连续测定１１次的相对标准偏差２．５％,可直接测定水体中μｇ／Ｌ级的铅。     

HPLC/ECD测定人血小板中5-羟色胺浓度

用ＨＰＬＣ／ＥＣＤ法测定血小板５－ＨＴ,运用 ＷａｔｅｒｓμＢｏｎｄａｐａｋ Ｃ柱,３,４二羟基苄胺（ＤＨ－ＢＡ）作内标,以 ０.０７ ｍｏｌ／Ｌ乙酸钠缓冲液＋乙腈为流动相（２０＋１）,每１Ｌ缓冲液含 ０．０５ ｍｏｌ／Ｌ柠檬酸、２．５ ｍｍｏｌ／Ｌ庚烷磺酸钠、０．１ｍｍｏｌ／Ｌ Ｎａ_２ＥＤＴＡ,流速０．８ ｍＬ／ｍｉｎ。ＤＨＢＡ和 ５－ＨＴ的保留时间分别为５．４和１１．５ ｍｉｎ,线性范围为０．０２５～１ｍｇ／Ｌ（ｒ＝ ０．９９９７）。５－ＨＴ日内 ＲＳＤ低于１．８７％,日间ＲＳＤ低于８．５４％,方法回收率为１００．４％±２．３％。提示本方法快速简便,灵敏准确,适用于临床基础研究。     

1-(2-噻唑偶氮)-2-萘酚螯合物反相高效液相色谱法分离测定铜(Ⅱ)、铁(Ⅱ)和镍(Ⅱ)

以１－（２－噻唑偶氮）－２－萘酚（ＴＡＮ）作柱前显色剂，于ＯＤＳ柱上，用内含０．１ｍｏｌ／ＬＬｉＣｌ，５×１０－６ｍｏｌ／Ｌ ＴＡＮ和ＨＡｃ－ＮＨ４Ａｃ缓冲溶液（ｐＨ ５．５）的甲醇－水溶液（８０：２０，Ｖ／Ｖ）作流动相，流速为０．６ｍＬ／ｍｉｎ，并以紫外－可见检测器于５９０ｎｍ处进行检测，发展了一种ＲＰ－ＨＰＬＣ法同时分离测定铜（Ⅱ）、铁（Ⅱ）、镍（Ⅱ）的方法，方法灵敏度高，对于铜、铁、镍的检测限分别为１μｇ／Ｌ， ２ μｇ／Ｌ和 ０．４ μｇ／Ｌ。用于实际样品测定，结果满意。     

流动注射离子交换预浓集火焰原子吸收光谱法直接测定人尿中痕量镉

应用高效的流动注射在线离子交换预浓集火焰原子吸收光谱测定系统直接测定了人尿中痕量镉。选择２００μＬ锥形离子交换柱，内装多孔玻璃固定化的８－羟基喹啉离子交换剂，在ｐＨ９条件下样品流速为３．５ｍＬ／ｍｉｎ，４０ｓ装样，用２ｍｏｌ／ＬＨＣｌ洗脱，在分析速度为６０样／ｈ，获得３０倍的富集倍率。检出限为０．３μｇ／Ｌ。镉含量水平为４０μｇ／Ｌ的尿样，连续测定１１次的相对标准偏差为１．５％。尿标准参考物...?     

双硫腙螯合形成树脂分离富集地质样品中的微量金,铂,钯及其测定

研究了双硫腙螯合形成树脂的合成及其分离富集地质样中Ａｕ，Ｐｔ，Ｐｄ的条件。于ｐＨ１．５的ＨＣｌ介质中，Ａｕ，Ｐｔ，Ｐｄ定量吸附于Ｈ２ＤＺ形成树脂上与大量贱金属分离。用０．６ｍｏｌ／Ｌ的硫脲－０．１ｍｏｌ／ＬＨＣｌ洗脱贵金属，回收率均在９４％－１０６％之间。铁也部分上柱，用磺基水杨酸与酒石酸１：１联合掩蔽除去。     

18—冠—6修饰碳糊电极测定定金的研究

本文研究了１８－冠－６修饰碳糊电极测定金的条件，金在０．５ｍｏｌ／Ｌ ＨＣｌ－０．００５ｍｏｌ／Ｌ ＫＣｌ底液中富集，介质交换到０．０１ｍｏｌ／Ｌ ＨＣｌ中进行测定。金（Ⅲ）浓度在０．１～１．０μｇ／ｍＬ范围内呈线性关系，相对标准偏差为９．７％，检出限为２０ｎｇ／ｍＬ。可不经预先分离直接测定矿样中的金，结果良好。并研究了Ａｕ（Ⅲ）在１８－冠－６碳糊修饰电极上的还原机理。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

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.