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1.
尼龙-1010的聚集态结构   总被引:1,自引:0,他引:1  
用WAXD、DSC、方差-范围函数.密度测量等方法,研究了经不同热处理的尼龙-1010的聚集态结构.发现退火处理更有利于尼龙-1010结晶的生成和稳定,且尼龙-1010的结晶,有一个最佳的热处理温度.在该温度附近,尼龙-1010的结晶度和微晶尺寸里最大值.  相似文献   

2.
汞电极表面电荷的快速估算   总被引:1,自引:0,他引:1  
本文报导了用交流示波极谱快速估算电极表面电荷的方法。该方法使用仪器简单,测量快速,操作简便,在吸附研究中很有用处。  相似文献   

3.
论述了铵梯脲混合炸药中改性硝酸脲和硝酸铵组分含量的一种快速准确的化学分析测定方法。该法在研制和生产铵脲类炸药的过程中,对选择最佳配比,控制生产和质量把关等有着重要的指导作用。同时笔者对测定方法,反应原理,影响因素等作了深入的探讨与研究。  相似文献   

4.
1,1,1-三氟-2-溴-2-氯乙烷(4)(简称氟烷)是1956年问世的一个高效低毒内吸入麻醉剂,我国于六十年代初期开始生产并供临床使用。七十年代初,长海医院发现某批氟烷麻醉剂在临床使用时有明显毒性,要求对毒性物质进行鉴定。该麻醉剂是经下述工艺生产的:  相似文献   

5.
Based upon the analyses of the sedimentary characteristics, the parallelism of longitudinal streams of the netty drainage system in Shanghai coastal plain to the ancient shorelines, the hydrodynamics in the northern bank of the Hangzhou Bay and the distribution of sites of ancient cultural remains, this paper indicates that during the period of 7000—4000 a B. P., the south spit of the Changjiang River mouth developed southward, and only stretched to the nearshore area of Jinshanwei. The southern end of the spit was a compoundrecurved one. In addition, the evolution of the shoreline west of Jinshanwei during the same period is discussed.  相似文献   

6.
一水合二甲基—氢代—2—(1,3一二磺酸单钠硫代丙基)铵是我国开发成功的一种仿生性沙蚕毒系的新杀虫剂,商品名为杀虫单[J]。农业上有广泛的用途。其结构式为:  相似文献   

7.
脱色阴离子交换剂的再生研究   总被引:1,自引:0,他引:1  
提出一种新的离子交换剂再生理论,即吸附物的脱附依靠离子交换和络合的协同效应完成.以二价钙离子为再生剂,对糖液脱色用的阴离子交换树脂和阴离子交换纤维进行再生,并与传统的碱性钠盐相比较,研究证明钙离子为再生剂的工艺,具有低成本、无污染的特点.  相似文献   

8.
In the present paper, in accordance with the exoskeleton structure, the method of Q-mode cluster analysis is used for a taxonomic study of 17 orders (suborders) of the Tritobita that was established or adopted by H. J. Harrington (1959), J. Bergstrm (1973), and R. A. Fortey and R. M. Owens (1975). The author suggests that the Trilobita be subdivided into 9 orders and 14 suborders, i. e. order Agnostida Kobayashi, 1935 (suborder Agnostina Salter, 1864 and suborder Eodiscina Kobayashi, 1939), order Redlichiida Richter, 1933 (suborder Redlichiina Richter, 1933, suborder Bathynotina Lochman-Balk, 1959 and suborder Olenellina Resser, 1938), order Corynexochida Kobayashi, 1935, order Ptychopariida Swinnerton, 1915 (suborder Ptychopariina Richter, 1933, suborder Proetina Fortey & Owens, 1975, nom. transl, ex Proetida Fortey & Owens, 1975 and suborder Calymenina Swinnerton, 1915, emended herein), order Illaenida Jaanusson, 1959 (suborder Illaenina Jaanuson, 1959 and suborder Asaphina Salter, 1864, emended herei  相似文献   

9.
The photo-oxidative degradation process of polypropylene film containing iron ions was investigated via FTIR and absorbance substraction technique. It is shown that the iron ions play an important role in the decomposition of hydroperoxide and the increase of the degradation rate of polypropylene film. The amorphous region of PP film undergoes degradation prior to the crystalline one.  相似文献   

10.
In attempting to study the phototherapeutic action and the photosensitized oxygenation mechanism, we have determined the crystal structure of the main oxidized product of hypocrellin A (HA). It was crystallized in monoclinic system with space group P2_1. The cell data are: a=10.030(3), b=8.877(3), c=15.764(5), β=104.50(2)°, Z=2. The crystal structure has been determined by direct method and refined to a final R of 0.055 based on the 1408 observed reflections with l>2.5σ(Ⅰ). The photooxidized product is composed of a heptacyclic aliphatic hydrocarbon connecting with two α-naphthoquinone derivatives as its skeletal molecule. No peroxidic linkage has been found. On the basis of the crystal structure determined, we have deduced part of the process of formation of the oxide, ⅰ. e. firstly, the peroxide was formed by photocycloaddition of oxygen molecule to Hypocrellin A, then thermodissociation took place to form a stable oxide.  相似文献   

11.
国产732型阳离子交换树脂吸附L-精氨酸的特性   总被引:9,自引:0,他引:9  
考察了溶液中氯化钠和氯化铵浓度、pH值、温度对732阳离子交换树脂吸附L-精氨酸的影响规律。结果表明:随着无机盐浓度的增大L-精氨酸的吸附率急剧降低,且盐浓度在大于1.0mol/L时几乎无法吸附;在低于等电点下,随着pH值的下降L-精氨酸的吸附率增大;适当升高温度,有助于提高L-精氨酸的吸附率。  相似文献   

12.
本文应用外部电容耦合式聚合装置,研究了α—蒎烯等离子体聚合规律。通过元素分析,裂解色谱-质谱、红外光谱和接触角测定等方法测定了聚合物的结构和性能。  相似文献   

13.
含咪唑功能基螯合树脂的研究进展   总被引:1,自引:0,他引:1  
咪唑环是一种含有两个配位原子的功能基,能与重金属离子形成稳定配合物。将其接枝到有机或无机高分子上,制得的含咪唑功能基的螯合树脂,不仅对重金属离子表现出良好的吸附选择性能,且回收操作简单、回收利用率高。本文对该类螯合树脂的研究进展进行了综述。  相似文献   

14.
一种简化的重氮化法制备固定化酶的载体合成方法   总被引:2,自引:0,他引:2  
重氮化法是固定化酶时常用的一种方法。用多孔玻璃等无机物作载体时,一般是先用g-氨丙基三乙氧基硅烷与多孔玻璃等载体反应[1,2],生成烷基胺玻璃,然后与对硝基苯酰氯反应,产物经过还原,生成带有芳胺的衍生物,最后进行重氮化。本文通过烷基胺与对氨基苯甲酸反应,直接生成芳胺的衍生物,比常用的方法缩短了一步。通过在新合成的载体上对木瓜蛋白酶进行固定化,研究了固定化条件对酶活力回收的影响,最适固定化条件如下:pH为7.0,时间为6h,酶量为240mg/g载体,并比较了固定化酶和溶液酶的有关性质,考察了固定化酶的操作稳定性。结果表明,用这种方法合成的载体固定化酶,其对热稳定性、操作稳定性及产率都比较理想。  相似文献   

15.
含氮给体结构对丙烯腈电荷转移光聚合的影响   总被引:1,自引:0,他引:1  
<正> 对于正性烯类单体,主要是乙烯基咔唑的电荷转移聚合,诚田已作过详细综述。负性烯类单体的电荷转移聚合主要研究的单体是丙烯腈(AN)及甲基丙烯酸甲酯(MMA)。Barton等研究了芳烃为引发剂的MMA光聚合。我们研究了芳胺为引发剂的光聚合。 芳胺,尤其是芳叔胺,是较强的电子给体,与负性单体在光照下经激基复合物而引发聚合,我们的实验表明,吡啶及其同系物(喹啉与吖啶)并不象吡咯及其同系物(吲哚与咔唑)那样有效地引发AN等负性单体的光聚合(见表1)。从图1所示的结构看,它们有  相似文献   

16.
The redox reaction between N-vinylcarbazole (NVC) and various oxidants including Ce(Ⅳ), Fe(Ⅲ)and benzoylperoxide in methanol proceeds via the initial formation of the NVC N-cation radical which in turn leads to the formation of the NVC cyclic dimer, trans-1,2-dicarbazylcyclobutane. Molecular oxygen and a few arylamines are able to accelerate the rate of the formation and increase the yield of the dimer. The mechanism of this process and the functions of oxygen and arylamines are presented as follows: The participation of molecular oxygen is to facilitate the dissociation of the resulting reduced metal ion and the NVC N-cation radical ion pair or charge transfer complex, thereby releasing the free NVC N-cation radical and increase the rate of the formation and yield of the dimer. The arylamine in this reaction between NVC and oxidants can be viewed as electron transfer agent between NVC and the oxidant. Because the amines are present in small amount relative to the oxidants and can be regenerated in pr  相似文献   

17.
混床再生剂的纯度和阴、阳树脂的混合程度会严重影响到混床出水水质.用高纯碱替代工业碱再生混床的阴树脂;采用反常规均粒混床树脂;对混床树脂采用特殊的再生和输送方法等措施均可提高出水水质.  相似文献   

18.
Figure-ground discrimination and pattern discrimination represent one of the most important problems in computer vision. Based on computational neuronal network model proposed by Reichardt et al. for figure-ground discrimination in the visual system of the fly, entire systematic computer simulations were carried out under nonstationary conditions. Results show that the model network and simulations have predictive power for behavioural experimental results. This paper proposes that motion perception and elementary pattern discrimination in human visual system may be mediated by some kind of figure-ground system with movement detectors as input layer.  相似文献   

19.
TECTONIC FRAMEWORK OF THE CONTINENTAL BASEMENT OF SOUTHEAST CHINA   总被引:8,自引:0,他引:8  
The chronology and tectonic evolution model of the continental basement in southeast China margin is an important debatable geological subject. The Cathaysia is shown in this paper to be in accordance with many geological facts and also with the age data obtained by multi-dating method. Its age has been determined to range from 900 to 2000 Ma. The age of the unconformity plane in the Cathaysia is 1400 Ma. The collision and suture between the Jiangnan oldland and the Cathaysia took place during the early Jinning Period. Toward Jiangxi, Hunan, Guangdong and Guangxi, these two continents gradually opened to form a residual oceanic basin. The sedimentation centre of the basin continuously migrated southwestward from the Jinning through the Caledonian Period, and finally closed in the Guangxi Movement and Dongwu Movement. The drift-rotation of the Cathaysia after the Jinning Period has been inferred.  相似文献   

20.
苦荞粉提取液中黄酮类化合物含量测定方法的选择   总被引:6,自引:0,他引:6  
通过硼酸-柠檬酸法、硝酸铝-亚硝酸钠-氢氧化钠法、氯化铝-乙酸钠法及芦丁法测定苦养粉中黄酮类化合物含量的比较,试验结果表明,芦丁法仅可测定苦荞提取液中部分黄酮类化合物的含量,而氯化铝法和硼酸-柠檬酸法无法将黄酮类化合物全部络合,试验选择硝酸铝法作为苦荞粉中黄酮类化合物的含量测定方法。  相似文献   

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