聚丙烯酸-g-非离子性聚氨酯接枝共聚物的合成及其在铬鞣中的应用研究

为了解决制革工业中的铬污染问题,制备了一种高分子型的高吸收铬鞣助剂,测定了其耐酸、耐铬离子交联特性,并应用与铬鞣工序中降低废液中铬含量。     

铬鞣液组成的研究方法进展

研究铬鞣液的组成及各种铬配合物在铬鞣过程所起的作用,对于阐明铬鞣机理和实际的铬鞣操作过程有重要的指导意义。对国内外研究铬鞣液组成所采用的主要的研究方法及其研究成果加以总结归纳,并对各种方法的特点作简要评述。     

与铬鞣有关的胶原化学研究进展

本文在回顾与制革有关的生皮胶原结构的基础上, 概述了铬鞣过程胶原与铬(?) 之间的作用, 并对近年来利用胶原计算机模型探讨鞣制反应和以提高铬鞣有效性为目的的胶原修饰化学的研究状况及其发展前景作简要论述。     

倒数示波计时电位滴定法测定鞣液中铬

倒数示波计时电位滴定法测定鞣液中铬郑建斌，白育伟，胡娟，朱俊杰，高鸿（西北大学化学系西安，７１００６９）（南京大学化学系南京，２１０００８）关键词倒数示波计时电位滴定，皮革鞣液，铬在皮革鞣制过程中，鞣液中铬含量的高低直接影响成革或毛皮板的质量和规格。...     

聚合物—皮革复合材料的研究：Ⅰ.丙烯酸酯单体在铬鞣猪皮中的聚合过程

采用Ｋ＿２Ｓ＿２Ｏ＿８－ＮａＨＳＯ＿３引发体系，研究了丙烯酸乙酯（ＥＡ）、甲基丙烯酸丁酯（ＢＭＡ）及其二元混合单体（ＥＡ－ＢＭＡ）在铬鞣猪皮中的聚合过程，考察了反应温度、时间、单体浓度和铬鞣猪皮的部位不同对反应的影响，初步探讨了改性过程的反应机理。     

电位滴定法测定工业废水中铬

报道了以氨三乙酸(NTA，活化剂)存在下，Mn(Ⅱ)催化高碘酸钾氧化孔雀绿的反应指示终点，孔雀绿电极作指示电极用催化电位滴定法测定工业废水中铬的方法。该法不需对样品进行复杂分离，操作简单方便，终点灵敏、准确度高，重现性较好。试验对鞣革废水及电镀废水中的铬进行测定并与火焰原子吸收光谱法比较，结果满意。用标准加入法测得的平均回收率为99．62％，RSD为0．94％。     

催化电位滴定法测定铬鞣剂中铬(Ⅲ)

报道了以氨三乙酸存在下锰(Ⅱ)催化KIO4氧化结晶紫的反应指示终点,结晶紫电极作指示电极用催化电位滴定法测定铬鞣剂中Cr(Ⅲ)的方法。该法终点灵敏、准确度高、重现性好,结果满意,用标准加入法测得的平均回收率为100.03%,RSD为0.24%。     

催化电位滴定法测定铬鞣中铬（III）

报道了以氨三乙酸存在下锰（II）催化KIO4氧化结晶紫的反应指示终点,结晶紫电极作指示电极用催化电位滴定法测定的铬鞣剂中Cr(III)的方法,该法终点灵敏,准确度高,重现性好,结果满意,用标准加入法测得的平均回收率为100．03％,RSD为0．24％。     

新型阻燃性氨基树脂鞣剂的合成

现有的阻燃剂产品多数分解温度低,难溶于水,不易渗透皮革纤维。本文合成的季戊四醇二氢酯羟甲基化三聚氰胺树脂具有高效的阻燃作用,又具有三聚氰胺树脂鞣剂独特的鞣革作用。本文考察其合成工艺条件及其对产品性能的影响因素。     

氯铬酸甲铵/硅胶载体氧化剂的制备及其对醇的氧化研究

利用硅胶作载体，负载氯铬酸甲铵盐制备了一种新的载体铬(Ⅵ)氧化剂。该试剂制备方法简单、性质稳定。可在多种反应介质中对伯醇和仲醇氧化，高收率得到相应的醛和酮，反应操作简单，提纯方便。     

Synthesis of 1H-2,3-dihydropyrrolizine derivatives as precursors of bifunctional alkylating agents

Two 1H-2,3-dihydropyrrolizine derivatives bearing a nitro group at the 6 position have been synthesized and an improved method for nitrating pyrroles using potassium nitrate in trifluoroacetic acid was developed. An efficient, two-step synthesis of the butterfly pheromone, Danaidone, was also developed with an overall 33% yield.     

Perspectives in nonsteroidal anti-inflammatory agents

Among numerous nonsteroidal anti-imflammatory agents synthesized in the past few years, various analogs of indomethacin, phenylacetic acid and heteroarylacetic acid have reached the stage of clinical evaluation. Their biochemical mechanisms of action are exemplified by the broad activity profile of indomethacin which includes inhibition of mediators and enzymes, effects on cell membranes, and, most recently, inhibition of prostaglandin biosynthesis. The importance of pharmacodynamic properties to clinical efficacy was clearly demonstrated in some cases. Several candidates were eliminated because of their side-effects. A group of α-methylarylacetic acids showed a high degree of stereospecificity in their potency and metabolisms in vivo, as well as inhibition of prostaglandin synthetase and albumin binding in vitro. Extrinsic Cotton effect provides a sensitive technique in the study of interactions of these drugs with biopolymers. Competitive binding and antagonistic interactions between nonsteroidal drugs, particularly salicylate, were observed in vitro and in vivo. Progress in salicylate research was marked by the synthesis of flufenisal as a new derivative with enhanced potency and longer duration of action. Several fenamate analogs and new chemical types have shown promise in preliminary clinical trials. Various immunological approaches are under investigation for the treatment of rheumatoid arthritis. Newer concepts are still needed to achieve more effective control of arthritic disorders.     

Determination of sunscreen agents in cosmetic products by supercritical fluid extraction and high-performance liquid chromatography

A rapid supercritical fluid extraction (SFE) procedure for the isolation of five of the most common sunscreen agents (2-ethylhexyl-p-dimethylaminobenzoate, 2-hydroxy-4-methoxybenzophenone, 2-ethylhexyl-p-methoxycinnamate, 4-methylbenzylidene camphor and 4-tert.-butyl-4′-methoxydibenzoylmethane) from cosmetic products is described. Investigation of the factors affecting the extraction efficiency in SFE indicated that sunscreen recoveries were affected mainly by the supercritical CO₂ pressure and by the trapping method. The sunscreens were analyzed by reversed-phase high-performance liquid chromatography after a 10-min extraction of the cosmetic product with CO₂ at 250 bar and 40°C, using sequential glass surface and C₁₈ sorbent as collection system. A quantitative comparison of SFE with a liquid extraction procedure was performed on commercial cosmetics. The SFE method yielded recoveries higher than 94.8% compared with conventional liquid extraction and exhibited a precision better than 5.3% relative standard deviation. Moreover, SFE minimized sample handling, reduced the consumption of harmful solvents and afforded a more effective purification of the cosmetic matrices.     

Characterization, synthesis and self-aggregation of (-)-alternarlactam: a new fungal cytotoxin with cyclopentenone and isoquinolinone scaffolds

(-)-Alternarlactam [(-)-1], a new promising cytotoxin against two human cancer cell lines, was isolated from an endophyte culture and synthesized (along with (+)-1) from readily available starting materials. The absolute configuration, chirality-activity relevance and self-aggregation of (-)-1 were assigned by a combination of synthetic, spectroscopic and computational approaches. The full characterization of the new fungal cytotoxin may provide valuable information in the discovery of new antitumor agents.     

In Situ Proteome Profiling and Bioimaging Applications of Small‐Molecule Affinity‐Based Probes Derived From DOT1L Inhibitors

DOT1L is the sole protein methyltransferase that methylates histone H3 on lysine 79 (H3K79), and is a promising drug target against cancers. Small‐molecule inhibitors of DOT1L such as FED1 are potential anti‐cancer agents and useful tools to investigate the biological roles of DOT1L in human diseases. FED1 showed excellent in vitro inhibitory activity against DOT1L, but its cellular effect was relatively poor. In this study, we designed and synthesized photo‐reactive and “clickable” affinity‐based probes (AfBPs), P1 and P2 , which were cell‐permeable and structural mimics of FED1 . The binding and inhibitory effects of these two probes against DOT1L protein were extensively investigated in vitro and in live mammalian cells (in situ). The cellular uptake and sub‐cellular localization properties of the probes were subsequently studied in live‐cell imaging experiments, and our results revealed that, whereas both P1 and P2 readily entered mammalian cells, most of them were not able to reach the cell nucleus where functional DOT1L resides. This offers a plausible explanation for the poor cellular activity of FED1 . Finally with P1 / P2 , large‐scale cell‐based proteome profiling, followed by quantitative LC‐MS/MS, was carried out to identify potential cellular off‐targets of FED1 . Amongst the more than 100 candidate off‐targets identified, NOP2 (a putative ribosomal RNA methyltransferase) was further confirmed to be likely a genuine off‐target of FED1 by preliminary validation experiments including pull‐down/Western blotting (PD/WB) and cellular thermal shift assay (CETSA).     

荧光法检测化学战剂

化学战剂,包括神经性毒剂(如沙林、VX)和糜烂性毒剂(如芥子气),属于剧毒化学品,能够严重危害国家安全和环境安全.因此,针对各类化学战剂,开发简单、快速、可便携化、高灵敏度和高选择性的荧光检测技术具有重要的意义.本文综述了近年来国内外荧光法检测化学战剂的研究进展,并对该领域所面临的挑战和未来发展方向进行了总结和展望.     

Platinum(II)–Gadolinium(III) Complexes as Potential Single‐Molecular Theranostic Agents for Cancer Treatment

Theranostic agents are emerging multifunctional molecules capable of simultaneous therapy and diagnosis of diseases. We found that platinum(II)–gadolinium(III) complexes with the formula [{Pt(NH₃)₂Cl}₂GdL](NO₃)₂ possess such properties. The Gd center is stable in solution and the cytoplasm, whereas the Pt centers undergo ligand substitution in cancer cells. The Pt units interact with DNA and significantly promote the cellular uptake of Gd complexes. The cytotoxicity of the Pt–Gd complexes is comparable to that of cisplatin at high concentrations (≥0.1 mM ), and their proton relaxivity is higher than that of the commercial magnetic resonance imaging (MRI) contrast agent Gd–DTPA. T₁‐weighted MRI on B6 mice demonstrated that these complexes can reveal the accumulation of platinum drugs in vivo. Their cytotoxicity and imaging capabilities make the Pt–Gd complexes promising theranostic agents for cancer treatment.     

Tetraamine‐Derived Bifunctional Chelators for Technetium‐99m Labelling: Synthesis,Bioconjugation and Evaluation as Targeted SPECT Imaging Probes for GRP‐Receptor‐Positive Tumours

Owing to its optimal nuclear properties, ready availability, low cost and favourable dosimetry, ^99mTc continues to be the ideal radioisotope for medical‐imaging applications. Bifunctional chelators based on a tetraamine framework exhibit facile complexation with Tc(V)O₂ to form monocationic species with high in vivo stability and significant hydrophilicity, which leads to favourable pharmacokinetics. The synthesis of a series of 1,4,8,11‐tetraazaundecane derivatives ( 01 – 06 ) containing different functional groups at the 6‐position for the conjugation of biomolecules and subsequent labelling with ^99mTc is described herein. The chelator 01 was used as a starting material for the facile synthesis of chelators functionalised with OH ( 02 ), N₃ ( 04 ) and O‐succinyl ester ( 05 ) groups. A straightforward and easy synthesis of carboxyl‐functionalised tetraamine‐based chelator 06 was achieved by using inexpensive and commercially available starting materials. Conjugation of 06 to a potent bombesin‐antagonist peptide and subsequent labelling with ^99mTc afforded the radiotracer ^99mTc‐N4‐BB‐ANT, with radiolabelling yields of >97 % at a specific activity of 37 GBq μmol^?1. An IC₅₀ value of (3.7±1.3) nM was obtained, which confirmed the high affinity of the conjugate to the gastrin‐releasing‐peptide receptor (GRPr). Immunofluorescence and calcium mobilisation assays confirmed the strong antagonist properties of the conjugate. In vivo pharmacokinetic studies of ^99mTc‐N4‐BB‐ANT showed high and specific uptake in PC3 xenografts and in other GRPr‐positive organs. The tumour uptake was (22.5±2.6) % injected activity per gram (% IA g^?1) at 1 h post injection (p.i.). and increased to (29.9±4.0) % IA g^?1 at 4 h p.i. The SPECT/computed tomography (CT) images showed high tumour uptake, clear background and negligible radioactivity in the abdomen. The promising preclinical results of ^99mTc‐N4‐BB‐ANT warrant its potential candidature for clinical translation.     

核磁共振在对映体纯度测定中的应用

综述了核磁共振技术对映体纯度测定中的应用，它包括三个方面：（１）手性衍生剂法；（２）手性镧系位移试剂法；（３）手性溶剂法，对三种方法的测定机理和特点也做了讨论，全文共６５篇参考文献。     

Role of stabilizing agents in the formation of stable silver nanoparticles in aqueous solution: Characterization and stability study

The stability of silver nanoparticles is controlled mainly by two major factors, namely, aggregation and oxidation. In the present study, silver nanoparticles were synthesized by using different series of reducing agents like a strong reducing agent (sodium borohydride), a mild reducing agent (tri-sodium citrate), and a weak reducing agent (glucose) with different capping agents, namely, polyvinyl pyrrolidone (PVP K 30), starch, and sodium carboxyl methyl cellulose (NaCMC). The synthesized silver nanoparticles were characterized by UV-Visible absorption spectroscopy, dynamic light scattering (DLS), atomic force microscopy (AFM), and anti-microbial activity. The particle size of silver nanoparticles varies in the following order: sodium borohydride < tri-sodium citrate < glucose. Combination of sodium borohydride–polyvinyl pyrrolidone and tri-sodium citrate-polyvinyl pyrrolidone yields stable silver nanoparticles compared to other combinations of reducing agents and capping agents. The stability results confirmed that a refrigerated condition (8°C) was more suitable for storage of silver nanoparticles. Anti-microbial activity of silver nanoparticles synthesized in a sodium borohydride–polyvinyl pyrrolidone mixture shows a larger zone of inhibition compared to other silver nanoparticles. Anti-microbial results confirmed that the anti-microbial activity is better with smaller particle size. The size and stability of silver nanoparticles in the presence of different combinations of stabilizing and capping agents are reported.