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1.
采用二次饱和-D最优设计的方法,研究Sr(NO3)2(x1)、KH2PO4(x2)和Na2B4O7·10H2O(x3)叶面喷施对秦油2号油菜的产量效应,获得回归方程:y=247.485+7.0048x1+2.29244x2—9.82646x3—0.2535x1x2—13.8524x1x3:—3.37475x2x3+27.0575X21—16.3036x22—8.7678x23结果表明St(NO3)2。有明显的增产作用.x1x3的交互作用(效应)最大.通过计算机模拟.其最佳因子组合为Sr(NO3),0.1%、KH2PO40.3%和硼砂0.01%,预计产量可达296.46kg/667m2.  相似文献   

2.
用水热合成出系列化合物MSn2(PO4)3(M=Na,K,NH4),该化合物具有NASICON型三维骨架结构,测得其晶胞参数为:(1)NaSn2(PO4)3,a=0.852692)nm,c=2.247(4)nm;(2)KSn2(PO4)3,a=0.8366(1)nm,c=2.356(4)nm;(3)NH4Sn2(PO4)3,a=0\8330(1)nm,c=2\390(5)nm.热分析结果表明,在较  相似文献   

3.
研究了CuSO4-KSCN-H2O2-NaOH反应体系,新发现了两种双节律现象。继而以流速作为扰动参数,对双节律Ⅱ中两个不同振荡态的不同流速点进行了周期调制,发现在临界区(接近实现OSS1→OSS2或OSS2→OSS1的流速点)只能实现单向跃迁;在OSS1态的kf^0=4.0mL/min和OSS2态的df^0=3.0mL/min,能实现在两振荡态间的双向跃迁,而且OSS2态比OSS1态稳定。  相似文献   

4.
双金属复合氧化物的结构与紫外阻隔性能   总被引:8,自引:1,他引:7  
双金属复合氧化物(CLDH)是一类发展迅速的无机层状材料的煅烧产物,在催化、吸附等领域已获长足进展[1],但作为紫外阻隔材料的性能研究尚鲜见报道.本文研究了不同双金属复合氧化物的紫外阻隔性能,结果发现二价金属离子为锌离子的CLDH具有良好的紫外阻隔性能.实验所用试剂均为分析纯.CLDH由NaOH,Na2CO3,MgSO4·7H2O,ZnSO4·7H2O,Al2(SO4)3·18H2O为原料,按文献[2]方法制备.ZnO+Al2O3复配物是按一定比例机械混合后,研磨,并在与CLDH相同的条件下煅烧…  相似文献   

5.
邱瑾 《分析化学》1998,26(5):552-555
建立了微生物代谢中硫酸根和硫代硫酸根的毛细管电泳分析方法.在选定实验条件下,各种阴离子(S2O2-3、SO2-4、CI-、NO-3、PO3-4)在4 min内达到完全分离,其中 S2O2-3和SO2-4迁移时间的相对标准偏差小于1%,峰面积的相对标准偏差小于5%.测定了4种菌株分别在两种培养基中的S2O2-3和SO2-4浓度随培养时间的变化.结果表明,其中一菌株在SK基中对S2O2-3有明显的氧化作用.  相似文献   

6.
α-磷酸锆层柱材料的制备、表征及其催化羰基化性能   总被引:4,自引:0,他引:4  
采用配体4-CH3SC6H4NH2插层的α-磷酸锆为插层主体,将Rh63+引入层状材料的层析之间制备了新型层柱催化材料Zr(HPO4)1.70(CH3SC6H4NH2)1.09(PO4)0.30Rh0.10.5.52H2O,其是距为2.36变为1.56nm,结晶度有所下降。  相似文献   

7.
通过η5-R~1C_5H_4(CO)_3MNa与η~5-R~2C_5H_4(CO)_3MNa(M=Mo,W)以及η~5-R~1C_5H_4(CO)_3MoNa与η~5-R~2C_5H_4(CO)_3WNa在Fe_2(SO_4)_3醋酸水溶液作用下的交叉氧化偶联反应,合成了7个新的非对称型金属单键化合物η~5-R~1C_5H_4(CO)-3Mo─Mo(CO)_3C_5H_4R~2-η~5(R~1,R~2:C(O)Me,CO2Et),η5-R1C5N4(CO)3W─W(CO)3C5H4R2-η5(R1,R2:C(O)Me,CO2Et;H,CO2Et)和η5-R1C5H4(CO)3Mo─W(CO)3C5H4R2-η5(R1,R2:C(O)Me,H;Et,C(O)Me;C(O)Me,n-Bu;CO2Me,n-Bu).用C/N分析、IR、1HNMR和MS表征了它们的结构,并对该氧化偶联反应的特点进行了讨论.  相似文献   

8.
改性SrTiO3陶瓷电容器材料的化学制备及电性研究   总被引:5,自引:0,他引:5  
本文采用(C4H9O)4Ti,Sr(NO3)2和Ni(NO3)3为原料制成柠檬酸多元配合物溶液,经过形成溶胶凝胶过程,在一定条件下进行热分解,获得组成为:0.91SrTiO3+0.09(Bi2O3.3TiO2)的陶瓷粉料,上述粉料掺入3mol%PbO,3Mol%Li2O和0.4mol%Rb2O后经混全,压片、干燥和烧结等步骤制成改性SrTiO3电容器材料,电性研究表明,用这种材料制成的电容器其介电  相似文献   

9.
研究了三氟甲基磺酸三甲基硅酯/三氯化锑((CH3)3SiOSO2CF3/SbCl3)复合引发体系对1,3 戊二烯的聚合行为.在(CH3)3SiOSO2CF3引发剂中加入SbCl3后,使聚合反应速率提高了24倍,产率从(CH3)3SiOSO2CF3引发的55%提高到80%以上,分子量提高17倍.在聚合体系中加入酮类后,产率和分子量相对于(CH3)3SiOSO2CF3/SbCl3配比为02:1时引发所得聚合物均呈下降趋势;但对不同的酮来说,随着酮的位阻的增大,聚合物的产率和分子量均增大.聚合物的1H NMR图和红外谱图数据均证明该聚合反应是通过(CH3)3SiOSO2CF3与体系中残存的水水解所形成的质子酸HOSO2CF3与SbCl3反应所形成的复合体系引发进行的.  相似文献   

10.
通过模拟结构因子计算将「(C4H9)4N」「Sc(NCS)6」.3.5H2O的空间群从正交晶系的pcab修正为立方晶系的pa3.将Sc(C17H13N2O2)3和「(H2O)10(OH)2Sc2」(C6H5SO3)4.4H2O从P1修正为C2/c。还将「Sc(NO3)3(H2O)3」.18-Crown-6的Pna21修正为Pnma。  相似文献   

11.
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%.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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%).  相似文献   

16.
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.  相似文献   

17.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

18.
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.  相似文献   

19.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

20.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

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