亚甲蓝修饰电极推动的血红素蛋白质直接电子转移反应

本文研究了几种血红素蛋白质包括牛血红蛋白, 人肌红蛋白和马心细胞色素C在亚甲蓝修饰电极上的非均相电子转移反应, 采用光透薄层光谱电化学法监测了血红素蛋白的直接电化学反应过程, 并进行了动力学研究。     

Hb-CTAB/GC电极的电化学行为研究及对NO的电催化检测

生物大分子的直接电化学研究是近年来研究的一个热点[1-3]。血红蛋白(Hb)是一种含血红素辅基的球型蛋白质,在生物体内起存储和运输氧气的作用,其所含的血红素辅基能发生得失电子的反应。但是,在血红蛋白分子中,一方面,血红素辅基被多肽链所包裹,使得血红素辅基不易接近普通电极     

浅析对血红素氧合过程认识的几个争议

血红蛋白是高等动物体内广泛存在的一种载氧蛋白,其活性中心是血红素,氧分子可与血红素中的铁可逆结合实现载氧。虽然人们对血红蛋白运载氧气的生物化学作用机制已有系统的认识,但由于研究方法的限制与分析数据的差异和分歧,对于血红素中心铁离子与氧分子配位的键合结构及相关性质变化仍存在诸多争议。本文就目前教学中存在的部分争议进行梳理总结,同时结合相关研究进展,对几种血红素氧合过程的结构模型进行合理性分析。     

有机化学综合实验:基于联二萘酚手性聚集诱导发光分子的合成、表征及性质研究*

将前沿科学成果引入大学有机化学综合实验课中,设计了基于联二萘酚手性聚集诱导发光分子的合成、表征及性质研究的有机化学综合实验。通过本实验,学生将掌握几类经典的有机反应,包括酚羟基保护、芳基甲酰化及缩合等反应的基本原理及操作,熟悉核磁共振、质谱等结构表征手段以及紫外-可见吸收光谱、荧光光谱以及圆二色光谱等性质表征技术,了解聚集诱导发光现象及机理。本实验综合了多种有机反应及性质表征技术,有利于提升学生的综合实验能力、科学研究思维并激发学生对科学研究的兴趣。     

乙炔的微型实验

利用气体实验微型装置设计了乙炔的制备、检验、收集和性质探究实验,主要包括实验用品、实验装置、操作步骤和安全注意事项等内容,具有简明易做、安全环保等优点,适宜于学生独立实验操作,有利于培养学生实验能力。     

双色流荧——基于氨气制备的鲁米诺双色荧光喷泉

基于氨气的制备、收集和尾气处理装置来设计溶液反应,利用氨气易溶于水导致瓶内外大气压瞬间失衡的性质实现喷泉实验。通过简单易行的操作,基于鲁米诺发光反应和无色酚酞溶液遇碱变色反应,成功实现了双色荧光喷泉实验。本实验的目的是普及基础化学中氨气的性质和鲁米诺遇血发出明亮的蓝光的特性,介绍鲁米诺发光的原理,让参观者解开悬疑侦探片中喷洒试剂就可以显示出肉眼不可见血迹的疑惑,切身感受化学之趣。     

跨学科融合实验：不锈钢皂的效果检验、原理探究与创新自制

不锈钢皂是用304不锈钢制作的肥皂,其有效性和原理存在争议。设计了跨学科融合实验,包括不锈钢皂的效果检验、原理探究与创新自制等3个主要环节。实验结果表明,不锈钢皂不能除菌,但能去除异味;其原理是物理吸附作用,而不是通过生成二价铁离子或三价铁离子与异味分子反应;可以通过物理打磨或化学腐蚀不锈钢表面、添加有效成分等多种方法自制不锈钢皂。实验基于生活情境中的真实问题,融合了化学、物理、生物、医学、通用技术等多学科知识和方法,培养学生解决跨学科问题的能力。     

稀土对血红蛋白载氧功能的抑制及与血红蛋白的作用

实验表明稀土离子可一定程序地抑制血红蛋白在低发压时释放氧的功能；所有稀土离子可导致血红蛋白和血红素辅基的荧光发射增强，使血红蛋白的α－螺纹旋含量减少和引起二级结构和构象的改变；稀土离子还可能干扰珠蛋白部分和血红素辅基正常的相互作用。     

基于自封袋和塑料点滴板的氯气性质实验设计

通过运用自封袋和塑料点滴板等微型装置设计实验,并选用浓度较稀的盐酸和次氯酸钠溶液反应来制取氯气,采用滤纸来扩大性质实验中溶液的接触面积,可以很好地完成氯气的氧化性、氯气与碱反应、氯水的漂白性以及氯离子的检验等实验。该微型实验设计绿色环保,操作简便。     

苜蓿豆血红蛋白合成的转译调节作用

本文对不同年龄的苜蓿根瘤的豆血红蛋白mRNA的转译活性进行了比较,证明苜蓿豆血红蛋白mRNA活性不受瘤龄的影响。苜蓿豆血红蛋白的抗血清或其IgG与豌豆豆血红蛋白有免疫反应;但与大豆豆血红蛋白没有这种反应。在体外转译系统中,将苜蓿豆血红蛋白加到其本身的和豌豆豆血红蛋白的mRNA转译系统中,则抑制了两者的转译作用。加入大豆豆血红蛋白、牛血红蛋白,则两者的转译作用不受影响。血红素可以提高豆血红蛋白的合成。实验证明豆血红蛋白的合成具有转译水平上的自动调节作用。     

Versatile microfluidic complement fixation test for disease biomarker detection

The complement fixation test (CFT) is a serological test that can be used to detect the presence of specific antibodies or antigens to diagnose infections, particularly diseases caused by microbes that are not easily detected by standard culture methods. We report here, for the first time, a poly(dimethylsiloxane) (PDMS)/glass slide hybrid microfluidic device that was used to manipulate the solution compartment and communication within the microchannel to establish sampler and indicator systems of CFT. Two types of on-chip CFT, solution-based and solid phase agar-based assays, were successfully demonstrated for biomarker carcinoembryonic antigen (CEA) and recombinant avian influenza A (rH7N9) virus protein detection. In addition, the feasibility of the on-chip CFT in assaying real biopsy was successfully demonstrated by specifically detecting rH7N9 and CEA in human serum. The results demonstrated that the miniaturized assay format significantly reduced the assay time and sample consumption. Exemption from protein immobilization, blocking, complicated washing steps and expensive enzyme/fluorescein conjugates highlights the merits of on-chip CFT over ELISA. Most attractively, the on-chip agar-based CFT results can be imaged and analysed by smartphone, strengthening its point-of-care application potential. We anticipate that the on-chip CFT reported herein will be a useful supplemental or back-up tool for on-chip immunoassays such as ELISA for disease diagnosis and food inspection.     

t,F显著性检验应用中的一个问题

文章就ｔ，Ｆ显著性检验在同一个问题上检验判断的不一致性，提出在对一种分析结果（或测试结果）实施鉴定时，有必要同时进行ｔ，Ｆ的联合检验，而只有当联合检验一同被接受之后，所作用出的判定结论才是完整和可信赖的。     

Rheological and transport properties of sulfonated polyacrylamide hydrogels for water shutoff in porous media

In this research, an optimal hydrogel, based on sulfonated polyacrylamide, was synthesized by statistical design of experiments using central composite method. This new hydrogel composed of sulfonated polyacrylamide (AN125VLM) and chromium triacetate as copolymer and crosslinker, respectively. The bottle and rheological tests were conducted to investigate the gelation time, thermal stability, gel strength and also ultimate elastic modulus, complex modulus, and yield stress. It was found that copolymer concentration had the main effect in both rheological and transport properties of hydrogels. The sample prepared at optimum condition, i.e. copolymer concentration of 26,340 ppm and crosslinker/copolymer ratio of 0.12, had an ultimate elastic modulus of 29.9 kPa, yield stress of 800 Pa, and complex modulus of 32 kPa. A coreflooding test through fracture was carried out to examine the optimum gel performance in a porous media. A value of 483 for the residual resistance factor ratio of water to oil confirmed the high ability of the hydrogel in reducing the relative permeability of water to oil in fractured media. Copyright © 2014 John Wiley & Sons, Ltd.     

5-HT1A Serotonergic, α-Adrenergic and Opioidergic Receptors Mediate the Analgesic Efficacy of Vortioxetine in Mice

Vortioxetine is a multimodal antidepressant drug that affects several brain neurochemicals and has the potential to induce various pharmacological effects on the central nervous system. Therefore, we investigated the centrally mediated analgesic efficacy of this drug and the mechanisms underlying this effect. Analgesic activity of vortioxetine (5, 10 and 20 mg/kg, p.o.) was examined by tail-clip, tail-immersion and hot-plate tests. Motor performance of animals was evaluated using Rota-rod device. Time course measurements (30–180 min) showed that vortioxetine (10 and 20 mg/kg) administrations significantly increased the response latency, percent maximum possible effect and area under the curve values in all of the nociceptive tests. These data pointed out the analgesic effect of vortioxetine on central pathways carrying acute thermal and mechanical nociceptive stimuli. Vortioxetine did not alter the motor coordination of mice indicating that the analgesic activity of this drug was specific. In mechanistic studies, pre-treatments with p-chlorophenylalanine (serotonin-synthesis inhibitor), NAN-190 (serotonin 5-HT_1A receptor antagonist), α-methyl-para-tyrosine (catecholamine-synthesis inhibitor), phentolamine (non-selective α-adrenoceptor blocker), and naloxone (non-selective opioid receptor blocker) antagonised the vortioxetine-induced analgesia. Obtained findings indicated that vortioxetine-induced analgesia is mediated by 5-HT_1A serotonergic, α-adrenergic and opioidergic receptors, and contributions of central serotonergic and catecholaminergic neurotransmissions are critical for this effect.     

我国台湾学科能力测验中自然科学选择题的设置及评价

我国台湾学科能力测验自然科学的题型全部为选择题,通过增加选项数目、增加多项选择题比例、改变多项选择题编排模式、改变计分方式、改变题量与总分关系等可以减少选择题存在的强猜现象、无法考查思维过程及无法顾及学生差异性等不足,改善了选择题的考查评价功能,使考试更加公平科学,可以为我国大陆即将全面铺开的学业水平考试选择题部分的设计提供参考。     

以科技论文为素材的高中化学试题命制策略

命制模拟试题时,教师一般会选择化学科技论文作为试题的背景材料。通过分析近3年江苏高考化学试题,可以看出流程图题考查的基本情况。以江苏某市高考模拟化学卷为例,从4个维度阐述了以科技论文为素材的高中化学试题的命制策略：选择合适的命题背景素材;将文字内容巧妙地转化为工艺流程图;建立背景素材与试题考查之间的联系;精心设计试题设问。根据命题实践提出命制试题的关注点。     

塑料多轴冲击标准与试验技术探讨

分析比较了ISO 6603-2和ASTM D3763中关于塑料多轴冲击试验方法的异同,着重讨论了这些标准在测试技术上的不同要求,探讨了试验机性能对试验结果的影响,并提出了对试验机测控系统软硬件设计的技术要求。     

Strain hardening test on the limits of Slow Crack Growth evaluation in high resistance polyethylene resins: Effect of comonomer type

Long term performance assessment of polyethylene pipes is an issue that has greatly increased in importance in recent years due to the incorporation in the market of high resistance to crack polyethylene grades (PE100RC), where established Slow Crack Growth (SCG) evaluation using traditional tests such as Full Notch Creep Test (FNCT) or Pennsylvania Notch Tensile (PENT) Test is insufficient. The development in recent years of fast evaluation techniques such as Strain Hardening (SH) modulus has opened an important alternative for quick SCG evaluation since it correlates well with other conventional tests such as FNCT and PENT. In this work, a large number of commercial and experimental polyethylene pipe resins with different comonomer types were evaluated in order to define their SH values to rank the resins as PE100 or PE100RC. A relationship is proposed that utilizes SH test results to estimate the SCG resistance of PE pipes. 1-Butene copolymer resins display threshold SH values of 38 and 53 MPa that have been assigned to PE100 and 100RC grades, respectively. Moreover, dependence of the SH values on comonomer type used has been demonstrated. The experimental results show that 1-hexene copolymer resins exhibit higher SH values than 1-butene comonomer based resins.     

Chemical Analysis and Toxicity Tests of Organic Pollutants in Xi River Water and Suspended Sediment of Shenyang City

Abstract

In 1987, in a 10-day investigation, two kinds of raw water and their suspended sediment samples were successively collected from the upper and middle reaches of the Xi River. The water and the suspended sediment samples were prepared by filtration of the raw water through a 0.45 μm membrane. The pH values of the water samples were adjusted to neutral (pH 6.5), basic (pH 11.0) and acid (pH 2.0) and passed through three adsorption columns filled with GDX macroreticular resin (MRR). The organic pollutants were subsequently eluted from the columns with CH₂Cl₂. Suspended sediment samples were extracted with CH₂Cl₂ by Soxhlet extraction. Organic pollutants were separated on silica gel columns and analyzed by GC and GCMS and assayed for acute toxicity, Ames test response, and micronucleus test response. Over 200 organic pollutants in the river water and the suspended sediments were determined. More than 60 main pollutants were identified according to the results of the chemical analysis and toxicity tests.     

Fabrication and characterization of functional graded polyurethane foam (FGPUF)

In this study, functionally graded polyurethane foams (FGPUFs) were produced using a layer‐by‐layer casting technique. Discontinuous FGPUFs were fabricated by this method. The scanning electron microscopy was used to study the morphology of all specimens. The mechanical properties of the polyurethane foams (PUFs) were evaluated by compression, indentation force deflection, drop weight tests, and dynamic mechanical thermal analysis. Scanning electron microscopy micrographs taken from different zones of functionally graded material showed the variation of the morphology of cells as well as the suitable interfaces between the layers of PUF. Investigation of mechanical properties suggested that FGPUF specimens have an optimum behavior between other specimens in compression and indentation force deflection tests. The results of drop weight test showed that FGPUF samples behaved like an energy absorber (14.31 KN) in comparison to other PUFs. The results of dynamic mechanical thermal analysis data showed an improvement in glass transition temperature (T_g) to −47.2°C and stability of modulus of FGPUFs as temperature increases.