共价

The calculations reveal the different natures of the C-Cl and Si-Cl bonds and show that the barriers for the heterolysis processes in both cases are controlled by the resonance energy.

计算结果表明这两种分子在水溶液中的异解解离能取决于体系的共价-离子共振能RE_(C-I，在键解离过程中其共振能的丧失是反应解离能的主要来源。

We coupled the IgG of monoclonal antibody N34 specific to UK and the Fab of monoclonal antibody SZ-51 specific to the membrane protein GMP-140 of activated platelet. The bispecific antibody (N34 SZ-51) is able to bind UK and plasma-clot simutaneously. It enhanced plasma clot lysis 5 fold by HUK whereas it enhanced plasma clot lysis 38 times by LUK. UK in association with the bispecific antibody didn't decrease the concentration of fibrinogen in the assay supernatants.

利用抗体介导使纤溶酶原激活剂定向到血栓表面，可大大提高其纤溶作用，我们用双功能团试剂将抗尿激酶的单克隆抗体N34的IgG和抗活化血小板膜蛋白GMP-l40的单抗SZ-5l的Fab片段通过二硫键共价偶联，合成的双专一性抗体（N34-SZ-51）既具有血栓亲和性也具有尿激酶亲和性，从而增加了尿激酶对血栓的专一性，使高分子量尿激酶溶栓率提高了5倍，使低分子量尿激酶溶栓率提高了38倍之多，且不影响血浆中纤维蛋白原的含量。

It has been shown that proteins and enzymes can be bound covalently to freshly prepared magnetite in the presence of carbodiimide.

有研究显示，在碳化二亚胺的存在下，蛋白质和酶可以和新制备的磁体共价连接。

No cracks and holes had been detected. Presence of elements Ni, P and Si were in the simple state of metallic bond Ni, P element and covalent bond SiC, respectively.

元素存在形态主要表现为Ni和P以单质的形式存在，Si以共价健SiC的形式存在，Ni-Ni之间以金属键进行结合。

Calculations indicate that Ni-Ni interaction in Ni81B19 alloy is stronger than metallic bond in pure Ni. However, the Ni-Ni interaction in pure Ni is stronger than that in Ni80P20 alloy. Direct B-B contact in Ni81B19 alloys appears in our simulation, however no direct P-P contact in Ni80P20 alloys is found.

其次，在Ni的d电子和B的p电子之间存在着强烈的相互作用，形成Ni原子和B原子间的强共价作用。B和P的加入后使催化反应中的活性位Ni的活性d电子数增加，在合金中起修饰作用。

Moreover, it was shown that the dispersion ability of SWNT in aqueous solution had a significant improvement after coating with NOMA.

检测器件在每个修饰阶段的电学性能的变化证明了NOMA对SWNT的非共价糖基化修饰及用CNTFET来检测糖-凝集素特异性识别作用的可能性。

Reversible covalent modification The activity of many enzymes is alterd by the reversible making and breaking of a covalent bond between the enzyme and a small nonprotein group.

可逆共价修饰许多酶的活性随酶和小的非蛋白质基团之间共价键可逆性的生成和断裂而改变。

These processes include an intramolecular cleavage, covalent addition of cholesterol and/or palmitate, and conversion into a multimeric freely diffusible form.

这些加工修饰包括分子内裂解，胆固醇和/或棕榈酸的共价修饰以及自由扩散形式的多聚体的形成等。

These ingredients includes epidermal growth factor, hepatocyte growth factor, dimethyl sulfoxide, phenobarbital sodium and all trans-retinoic acid. We isolate and culture primary 10-weeks-old human fetal hepatocytes, observe hepatocytes form and its function markers. Inoculate hepatocytes with HBV Dane particles to observe if HBV susceptibility of fetal hepatocytes can be induced in vitro. To detect HBV covalently closed circular DNA within hepatocytes, we improve the existent PCR method.

基于上述假设，我们设计了10种培养条件，在自行设计的无血清培养基中添加不同的细胞分化诱导物，包括表皮生长因子、肝细胞生长因子、二甲基亚砜、苯巴比妥钠、全反式维甲酸等，分离孕10周龄人胎肝细胞进行原代培养，观测肝细胞形态及功能指标变化，并定时给予HBV感染，观察能否在体外诱导胎肝细胞出现HBV易感性；为检测肝细胞内HBV共价闭合环状DNA(covalently closed circular DNA，cccDNA)，我们改进了现有的PCR检测法。

Some of non-covalent interactions between the coils of DNA double strand may be involved in the solenoidal structure of DNA.

DNA链之间可能存在非共价相互作用以维持这种结构。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。