反应作用

Meanwhile, the concentration of Pb,Zn and other heavy metals is rather high in the oxidation zone and decreasesdownward to levels that are unbelievably low for Pb-Zn mine tailings. Theseobservations suggest that heavy metals should be re-immobilized by secondaryminerals, rather than primary minerals, in the oxidation zone, and could be leachedout from suboxic environment due to low rate oxidative dissolution which preventsthe precipitation of secondary minerals in significant amount. Thus, cover scenarioswhich establish a suboxic environment beneath the cover layer might not always beeffective in preventing heavy metal release from mine tailings.Sequential extraction studies indicate that, in addition to heavy metal leaching,oxidation of the mine tailings increased the mobility of residual Zn, and Cu, while Pb remains immobile due to the formation of anglesite (PbSO4). Using the seven-step extraction technique developed by Dold (J. Geochem. Explor., 2003, 80: 55-68), galena dissolves in significant amount at step 2 most probably due to the strong complexing of Pb2+ by acetate, while other metal sulfides dissolve at step 6, which suggest that this extraction technique could not be used to evaluate the mobility of lead in natural environment

重金属含量均低于新鲜尾矿，但以硬化层中的含量最高(Pb、Zn含量分别为0.47%和0.93%)，往下大幅度降低，表明尾矿风化过程中形成的次生矿物对Pb、Zn等重金属元素有较强的固定作用，而次氧化带的淋溶作用造成了金属元素的大量流失；(4)与新鲜尾矿相比，硬化层中铅的可迁移性大大降低，硬化层之下尾矿样品中铅的可迁移性也不同程度降低，这是由于硫化物氧化产生的硫酸根与尾矿中的铅反应形成铅矾(PbSO_4)的缘故；(5)氧化作用使尾矿中的zn、Cu等重金属的可迁移性不同程度地增大，其中对锌的可迁移性影响最大，铜的可迁移性与铁比较相似，铅则容易与硫化物氧化形成的SO_4~(2-)反应形成铅矾(PbSO_4)；(6)为了减少尾矿污染和修复矿山环境，人们提出了各种不同的尾矿覆盖方案，本文的研究结果表明，这些方法不一定能够有效地阻滞污染元素的迁移。

Pioneering work by Cohen and coworkers about T cell vaccination in the experimental autoimmune disease, has showed that the establishment of immune response against T cell vaccine, such as anti-idiotype T cells or anti -idiotype antibody, by the way of the upregulation of immune networks, and subsequently functional depression of autoimmune to self-antigen were made by vaccining mice or rate with the attenuated autoreactive T cells .

从研究TCV在防治自身免疫性疾病中的作用机制表明，人为的TCV免疫，建立了拮抗T细胞的免疫应答，使免疫网络产生上调作用，抑制了原有的或即将出现的相关T细胞的功能，由此推测，是否能够把同种反应性T细胞作为TCV，来建立抗同种免疫反应的内环境，诱导抗原特异性的同种免疫耐受或免疫低反应性。

The molecular weight of dextransucrase measured by SDS-PAGE was 170 kDa ,which was similar to the enzyme from Leuconostoc mesenteroides. The enzyme had an optimum temperature between 25and 30℃ and an optimum pH of 5.4. It was relatively stable in the range of pH 5.0 to 7.0, but the stability declined rapidly as soon as the temperature rose over 35℃.

以蔗糖为底物，酶促反应的最适温度为25～30℃，最适pH值为5.4，动力学常数Km值为10.43 mmol/L；酶活在pH 5.0～8.0较为稳定，在室温（25℃）保藏4 天仍有59%的酶活力，4℃保存7周酶活力仅下降一半，但在35℃以上失活很快；Ca2+对催化作用有较大的促进，Mg2+有微弱的促进作用，K+对催化反应无影响，Cu2+的抑制作用最强。

The experimental data demonstrated that there was a nasalward directional preference in oath OKN system under both close loop and open loop conditions, and the nasalward OKN gain evoked by stimulation of nasal retina was much higher than that at temporal retina. ms indicates that OKN nasalward preference is mairily derived from the nasal retina, i. e. the direct path1Vay of OKN dominates the indirect pathway in cat's OKN system. The gains of temporalward and nasalward OKN from temporal retina are much less than those of nasalward OKN from nasal retina. It is suggested that the indirect pathway of OKN in the cat only possesses a supplementary function, Which probably plays an important role in temporalward OKN eye-movments in relation to binocular vision.

实验结果显示：高速度刺激的闭环OKN反应及开环OKN反应均对鼻向运动刺激有明显的方向选择性；半侧视网膜刺激时，鼻侧半视网膜的鼻向OKN增益明显高于颞侧半视网膜的鼻向增益，说明猫的OKN眼动反应以跟踪鼻向运动为主，并且这种对鼻向运动刺激的选择性主要来源于鼻侧半视网膜，亦即来源于OKN直接通路；颞侧半视网膜的鼻、颞向眼动增益均明显低于鼻侧半视网膜的鼻向眼动增益，说明猫的OKN系统的间接通路在OKN眼动控制中起辅助作用，并可能主要对颞向OKN眼动起作用从而与双眼视觉功能相关。

But the effluent ammonium in the anoxic reactor, where enough NO2 were present, was equal to the blank system, and no ammonium was converted to such nitrogen compounds as NO2- and N2 by Nitrosomonas eutropha using NO2 as electron acceptor, which maybe caused by lack of the function bacteria. There were two ANAMMOX reaction pathways in the one-stage autotrophic nitrogen removal system. One way was that after part of NH4+ was oxidized to NH2OH under aerobic conditions, NH2OH and NO2- were converted to N2O under anaerobic conditions, at last N2O was further converted to N2 which realized the nitrogen removal; Another way was that at first NO2- was reduced to NH2OH, NH2OH reacted with NH4+ to form N2H4, which was further converted to N2 subsequently, realizing the nitrogen removal.

结果表明：单级自养脱氮系统内6.72%的氨氮是通过吹脱等物化作用去除的，不超过6.02%的氨氮是通过传统硝化反硝化途径去除的，87.26%左右的氨氮是由自养脱氮途径去除的，自养脱氮反应起主要脱氮作用；在足够NO2存在且缺氧的条件下，单级自养脱氮系统内的出水氨氮浓度与空白反应器相当，NH4+并没有被亚硝化单胞菌以NO2为电子受体氧化为NO2-和N2等化合物而得以去除，可能是因为系统内不存在该代谢功能的亚硝化功能菌；单级自养脱氮系统内存在两条ANAMMOX反应途径：其中一条途径即NH4+在好氧条件下被氧化为NH2OH后，生成的NH2OH与系统内的NO2-在缺氧条件下被转化为N2O，N2O则进一步被转化为N2而实现氮的去除；另外一条途径即NO2-首先被还原为NH2OH，生成的NH2OH则与系统内的NH4+反应生成N2H4，N2H4继续被转化为N2而实现氮的去除。

It was proved by IR spectroscopy that Zn2+ and hydrolyzed ion were chelated with polysilicic acid to produce the polymer of zinc-silicon. The reaction was not the simple physical blending,but the chemical reaction forming the inorganic polymer with special structure.

红外光谱证实了PZSS中Zn2+及水解Zn2+离子可与共存的聚硅酸起螯合反应生成锌硅聚合物，聚硅酸与Zn2+反应并不是单纯的物理混合加成作用，而是形成了具有特殊结构的无机高分子的化学反应，这种新型絮凝剂所具有的优良絮凝特性是由各物质间以化学作用为主的物理化学因素共同作用的结果。

It was proved by IR spectroscopy that Zn(superscript 2+) and hydrolyzed ion were chelated with polysilicic acid to produce the polymer of zinc-silicon. The reaction was not the simple physical blending, but the chemical reaction forming the inorganic polymer with special structure. The better flocculating efficiency was resulted mainly from the chemical and physico-chemical factors among the components.

红外光谱证实了PZSS中Zn(上标 2+)及水解Zn(上标 2+)离子可与共存的聚硅酸起螯合反应生成锌硅聚合物，聚硅酸与Zn(上标 2+)反应并不是单纯的物理混合加成作用，而是形成了具有特殊结构的无机高分子的化学反应，这种新型絮凝剂所具有的优良絮凝特性是由各物质间以化学作用为主的物理化学因素共同作用的结果。

Finally, the article discussed the possible mechanism of multi-phase electrochemical degradation of wastewater through the XPS spectrum of the used catalysts surface: In the acid solutions, the electro-generated O_2 may get electrons on the porous graphite cathode and then form H_2O_2, H_2O_2 may diffused to the surface of catalyst and reacted with its active part to produce OH, which in turn can destruct organics. The catalyst functioned as both the catalyst to decompose H_2O_2 and the flocculants to sedimentate the degraded waste.

最后全文结合研究反应后催化剂表面的XPS光电子能谱推断了该体系降解污废水可能的反应机理：在酸性条件下，石墨双阳极产生的O_2被多孔扩散性石墨阴极还原成H_2O_2，并通过扩散传质作用在催化剂的表面活性中心分解为强氧化性中间产物·OH，强氧化性攻击有机物，使其降解为小分子有机物或CO_2和H_2O，催化剂在体系中即起催化作用也起吸附、絮凝作用。

Veratryl alcohol could stimulate the oxidation of PR catalyzed by LiP, especially at higher molar ratios of H2O2 to PR, however, PR inhibited the LiP catalyzed oxidation of VA.

藜芦醇对LiP催化氧化PR的反应有促进作用，尤其是当H202与PR的摩尔比较高时这种促进作用更为明显；然而PR对LiP催化氧化VA的反应却有抑制作用。

Allogeneic and syngeneic fresh bone, autolyzed antigen-extracted bone, bone matrix gelatin, demineralized bone matrix were implanted into the muscle pouch of mice, at different times after implantation, the immunological, histological and alkaline phosphatase assay were conducted. The results revealed that all four kinds of allogeneic implants activated specific cellular and humoral immune responses, most notably in fresh bone group, the AAA, BMG and DBM inhibited the proliferation of the lymphocytes in vitro and BMG had the most powerful inhibiting action, allogeneic AAA, BMG and DBM might induce heterotopic osteogenesis in vivo, however, there were obvious difference in ALP and histomorphometry between allografts and isografts.

在小鼠肌肉内植入同种异体或同系新鲜骨、自消化抗原去除骨、骨基质明胶、脱钙骨基质，术后免疫学、碱性磷酸酶、组织学检查发现：4种同种异体植入物均可引发特异性细胞免疫反应和体液免疫反应，其中以新鲜骨移植引发的免疫反应最为显著；自消化抗原去除骨、骨基质明胶、脱钙骨基质在体外具有抑制淋巴细胞增殖的作用，骨基质明胶对淋巴细胞增殖的抑制作用最显著；同种异体与同系4种植入物在体内成骨活性有显著差异；自消化抗原去除骨、骨基质明胶、脱钙骨基质均有异位诱导成骨活性，其中骨基质明胶骨诱导活性最佳。

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。