SPR免疫竞争法研究小分子吗啡与其抗体间作用的动力学特征

表面等离子体共振技术(SPR)主要应用于生物大分子相互作用的研究,本文采用溶液竞争法,测定了小分子吗啡与其抗体作用的结合常数K₁,并计算了吗啡抗体与吗啡化牛血清白蛋白的结合常数K₂.证明了多抗对抗原的亲和力较单抗大,并表明大分子蛋白质的存在对抗体与待测物的结合有阻碍作用.     

钢渣与污泥协同资源化研究进展

钢渣和污泥作为传统大宗固体废弃物,始终面临处理成本高、回收利用率低等问题,但其内部含有大量可利用物质,具有较高的资源化利用价值,现已成为国内外的研究热点。为了提高钢渣与污泥绿色、高效、协同资源化利用,综述了近年来国内外钢渣在建筑、道路、水处理、农业等领域资源化利用的研究进展,立足固废无害化、减量化,从钢渣和污泥的资源化进行分析与总结,指出不同研究方法的特点和优劣,为固废资源化利用提供参考。并基于我国发展现状对钢渣与污泥资源化利用的未来发展方向进行了展望,以期为固废处理行业的良性发展提供一定的理论支撑。     

Competition STD NMR for the detection of high-affinity ligands and NMR-based screening

The reported competition STD NMR method combines saturation transfer difference (STD) NMR with competition binding experiments to allow the detection of high-affinity ligands that undergo slow chemical exchange on the NMR time-scale. With this technique, the presence of a competing high-affinity ligand in the compound mixture can be detected by the disappearance or reduction of the STD signals of a low-affinity indicator ligand. This is demonstrated on a BACE1 (beta-site amyloid precursor protein cleaving enzyme 1) protein-inhibitor system. This method can also be used to derive an approximate value, or a lower limit, for the dissociation constant of the potential ligand based on the reduction of the signal intensity of the STD indicator, which is illustrated on an HSA (human serum albumin) model system. This leads to important applications of the competition STD NMR method for lead discovery: it can be used (i) for compound library screening against a broad range of drug targets to identify both high- and low-affinity ligands and (ii) to rank order analogs rapidly and derive structure-activity relationships, which are used to optimize these NMR hits into viable drug leads.     

Overwhelming electrochemical oxygen reduction reaction of zinc-nitrogen-carbon from biomass resource chitosan via a facile carbon bath method

Developing high efficiency and low cost electrocatalysts is critical for the enhancement of oxygen reduction reaction (ORR), which is the fundamental for the development and commercialization of renewable energy conversion technology. Herein, zinc-nitrogen-carbon (Zn-N-C) was prepared by using biomass resource chitosan via a facile carbon bath method. The obtained Zn-N-C delivered a high specific surface area (794.7 cm²/g) together with pore volume (0.49 cm³/g). During the electrochemical evaluation of oxygen reduction reaction (ORR), Zn-N-C displayed high activity for ORR with an onset potential E₀ = 0.96 V_RHE and a half wave potential E_1/2 = 0.86 V_RHE, which were more positive than those of the commercial 20 wt% Pt/C benchmark catalyst (E₀ = 0.96 V_RHE and E_1/2 = 0.81 V_RHE). In addition, the Zn-N-C catalyst also had a better stability and methanol tolerance than those of the Pt/C catalyst.     

氮掺杂碳原位锚定铜纳米颗粒用于高效氧还原反应催化剂

与贵金属铂基电化学氧还原反应（ORR）催化剂相比,廉价的非贵金属催化剂引起了广泛的关注。本文以壳聚糖作为一种富含氮和碳元素的生物质资源,利用碳浴法成功制备了氮掺杂碳原位负载铜纳米颗粒（Cu/N-C）催化剂。纯壳聚糖碳化得到的样品N-C的比表面积为67.5 m²·g^-1、平均孔径0.14 nm、平均孔体积8.00 m²·g^-1,与之相比,Cu/N-C比表面积可达607.3 m²·g^-1、平均孔径为2.5 nm、平均孔体积为0.40 cm³·g^-1。通过密度泛函理论（DFT）进行计算表明,Cu(111)/N-C的自由能值低于N-C,更有利于氧还原催化进行。在0.1 mol·L^-1 KOH的介质中,Cu/N-C不仅表现出优异的起始和半波电势（分别为0.96 V和0.84 V）,而且还表现出了优异的抗甲醇性能和稳定性,并且Cu元素掺杂量达到1.67wt.%。     

Calcium Sulfite Solids Activated by Iron for Enhancing As(III) Oxidation in Water

Desulfurized gypsum (DG) as a soil modifier imparts it with bulk solid sulfite. The Fe(III)–sulfite process in the liquid phase has shown great potential for the rapid removal of As(III), but the performance and mechanism of this process using DG as a sulfite source in aqueous solution remains unclear. In this work, employing solid CaSO₃ as a source of SO₃²⁻, we have studied the effects of different conditions (e.g., pH, Fe dosage, sulfite dosage) on As(III) oxidation in the Fe(III)–CaSO₃ system. The results show that 72.1% of As(III) was removed from solution by centrifugal treatment for 60 min at near-neutral pH. Quenching experiments have indicated that oxidation efficiencies of As(III) are due at 67.5% to HO^•, 17.5% to SO₅^•− and 15% to SO₄^•−. This finding may have promising implications in developing a new cost-effective technology for the treatment of arsenic-containing water using DG.     

三种抗氧化物质与牛血清白蛋白的相互作用

运用荧光光谱(FS)、紫外光谱(UV)和超滤(UF)法, 研究了阿魏酸、毛蕊异黄酮及芒柄花素三种抗氧化小分子物质与牛血清白蛋白(BSA)的结合反应. 以Lineweaver-Burk双倒数方程和能量传递原理分别计算了三者与BSA反应的结合常数(K_LB)和结合距离(r)以及由热力学参数的计算判断了三种小分子物质与BSA结合的作用力类型; 以Scatchard方程计算了三种小分子与BSA的结合常数(K_a)和结合位点数(n); 并对阿魏酸与毛蕊异黄酮及芒柄花素的竞争结合反应进行了研究. 实验结果表明: 这三种物质能与BSA结合形成非共价复合物, 导致BSA内源性荧光的静态猝灭; 它们与BSA的结合能力随着极性基团的增多、分子体积的增大而减弱; 静电作用和疏水作用可能是它们与BSA结合的主要作用力; 阿魏酸与芒柄花素或毛蕊异黄酮会产生与BSA的竞争结合效应.     

中学生化学创新实验比赛的实践与思考

从3个方面介绍了高中生化学创新实验比赛的组织及开展：创新实验比赛的策划与准备,实验的试做与改进,实验比赛的开展与结果。总结创新实验比赛的意义：提高学生实验设计和操作能力,激发学生化学学习的兴趣,促进创新能力的培养。     

高中化学竞赛有机部分的学习方法和技巧

全国高中化学竞赛中,有机化学一直是竞赛内容的重要部分,其难度较大。因此,结合近年来全国高中化学竞赛试题阐述了基础有机化学反应、有机化学理论知识和有机化学反应历程3个模块的学习方法;总结了归纳法、逆推法、综合分析法等解答有机试题的技巧,从而帮助学生短时间内提高竞赛成绩。