二价

Meiotic pachytene bivalents were obtained from porcine testes using prolonged hypotonic treatment combined with high chloroform Carnory's fixative solution. Mitotic metaphase chromosomes were prepared from blood cell culture. Comparative studies on division index and length of pachytene bivalents and mitosis metaphase chromosomes showed that those of the former are 5 times higher and 3.42(1.87～5.98) times longer than the latter, respectively. Chromomere maps of bivalents are more abundant than mitotic metaphase G-bands, while they are correspondent with mitotic early-metaphase G-bands. The result was found by using the chromosome 12 as a sample.

以性成熟公猪睾丸和外周血为材料，采用长低渗、高氯仿卡诺固定液固定和外周血细胞培养制备减数分裂粗线期二价体和有丝分裂中期染色体，通过对二价体和有丝分裂中期染色体分裂指数和长度的比较研究，发现二价体的分裂指数和长度分别是有丝分裂中期染色体的5倍和3.42倍(1.87～5.98)；同时以12号染色体为例，比较了二价体上的染色粒结构带与有丝分裂中期染色体G-带，表明染色粒结构带比中期染色体G-带带纹丰富，而与早中期G-带带纹吻合。

In the presence of the combination of sulphuric and phosphoric acid, with sodium diphenylamine sulfonate as the indicator, standard solution of potassium dichromate was used to titrate total iron value.

试样以盐酸溶解后，在酸性介质中，先以氯化亚锡将三价铁大部分还原为二价，然后在钨酸钠指示下，再以三氯化钛将剩余的三价铁还原为二价，过量的三氯化钛以重铬酸钾氧化消除干扰，在硫磷混合酸存在下，以二苯胺磺酸钠为指示剂，用重铬酸钾标准溶液滴定全铁量。

Centromeres could be identified easily on the bivalents at diplotene, so it was convenient to analyse the karyotype.

结果表明，日本沼虾染色体数n=52，2n=104，据双线期二价体的相对长度、着丝点位置以及形态诸方面的特点分析了核型，共分为A，B，C，D4个染色体组，核型组成是N=37M+4ST+11T；初级精母细胞减数分裂前期I可分为细线期/偶线期、粗线期、双线期和终变期5个时期，双线期的二价体存在弥散阶段，核仁明显，且双线期二价体着丝点清晰，给核型分析带来了方便。

The quadrivalent was made of the normal 11 chromosome, the normal 18 chromosome, the translocated 11; 18 chromosome and the translocated 18; 11 chromosome.

精母细胞中SC分析，在早粗线期、中粗线期和晚粗线期精母细胞中，均发现22个常染色体SC和一个XY-二价体，即23个二价体；未发现22个二价体和一个单价体细胞，说明这条rob（21q；21q）染色体的两个臂完全配对形成发夹结构，形态上与正常SC一样，但与正常21号SC相比，其相对长度变短，由正常的1.5±0.1变为1.25±0.05。

As there were 8.69 bivalents in average occurred to be desynaptic, moreover, the most number of the desynaptic bivalents reached 12 at post diakinsis.

从品种轮回422的群体中发现一不育单株，经细胞学观察证明是发生了联会消失突变，由于该植株的花粉母细胞在减数分裂终变期晚期平均有8.69个二价体发生了联会消失，占二价体总数的72.4%，并且发生联会消失的最多二价体数目为12，根据联会消失的最多二价体数目

For pre-selection of iron compounds that ferrous sulfate, ferrous chloride, ferrous fumarate, carbonyl iron, amino acid chelated iron, iron asporotate, fenic chloride and ferric pyrophosphate were added in reconstituted skim milk to undergo in vitro digestion, respectively, and then the selected iron compounds were added in reconstituted whole milk to compare the iron bioavailability by estimating dialyzable ferrous iron, dialyzable total iron, nondialyzable and total ferrous iron, respectively.

取硫酸亚铁、反丁烯二酸亚铁、氯化亚铁、艰基铁、Iron asporotate、Amino acid chelated iron、氯化铁与焦磷酸铁等不同铁剂添加於脱脂还原乳中进行体外消化试验，并筛选生物利用性佳之铁剂分别添加於全脂还原乳中，以可透析二价铁、可透析总铁、未透析二价铁及总二价铁等作为评估之指标。

For pre-selection of iron compounds that ferrous sulfate, ferrous chloride, ferrous fumarate, carbonyl iron, amino acid chelated iron, iron asporotate, fenic chloride and ferric pyrophosphate were added in reconstituted skim milk to undergo in vitro digestion, respectively, and then the selected iron compounds were added in reconstituted whole milk to compare the iron bioavailability by estimating dialyzable ferrous iron, dialyzable total iron, nondialyzable and total ferrous iron, respectively.

取硫酸亚铁、反丁烯二酸亚铁、氯化亚铁、艰基铁、Iron asporotate、Amino acid chelated iron、氯化铁与焦磷酸铁等不同铁剂添加於脱脂还原乳中进行体外消化试验，並筛选生物利用性佳之铁剂分别添加於全脂还原乳中，以可透析二价铁、可透析总铁、未透析二价铁及总二价铁等作为评估之指標。

In this thesis, a series of complexes based on aromatic multicarboxylic acids have been successfully synthesized in solutions or under hydrothermal conditions. Their structure and properties are investigated.(1) Eight complex compounds have been synthesized and characterized by X-ray single crystal diffractive technology: The eight complexes are listed as following: [Cu242] complex 1 [Cd22(H2O)4]·4H2O complex 2 [Co(H2btc)(H2O)3] complex 3 [Co2(H2O)2]·H2O complex 4 [Ni22(H2O)4] complex 5 [Cu22(H2O)4] complex 6 [Co(H2biim)2(H2O)2](H2btc) complex 7 [Zn(H2biim)2(H2O)2](H2btc) complex 8 The structure of complex 1 is dinuclear complex resulted from weak interactions（0-D chain）; complex 2 is 1-D chain stucture result from interactions of water molecules; complex 3、4、5、6 are coordination polymers using hydrothermal synthses, where the first kind ligand is H4btc, the second kind ligand is phen and Co2+、Ni2+、Cu2+ as center ions, respectively. While the coordination enviroment of Co2+ is the same in complex 3, the coordination geometries around the Co atoms in complex 4 are obviously different because of the different reaction conditions. In complex 4, the 1-D chains are connected into 2-D layer through carboxy groups of ligand H4btc. The structures of complex 5、6 are 1-D chain stucture result from interactions of carboxy groups in ligand H4btc. Complex 7、8 are homeomorphy compounds. Either of them are linked to the 3-D chains through intermolecular hydrogen bonds. Each H4btc lose two protons and H2btc2- acts as negative electron balance.

合成了8个结构新颖的配合物，并用X-射线单晶结构分析方法确定了晶体结构，分别为： [Cu242] 配合物1 [Cd22(H2O)4]·4H2O 配合物2 [Co(H2btc)(H2O)3] 配合物3 [Co2(H2O)2]·H2O 配合物4 [Ni22(H2O)4] 配合物5 [Cu22(H2O)4] 配合物6 [Co(H2biim)2(H2O)2](H2btc)配合物7 [Zn(H2biim)2(H2O)2](H2btc)配合物8 配合物1是一个依靠弱作用连接的双核铜结构；配合物2借助水分子形成一维链状结构；配合物3、4、5、6是以H4btc为第一配体、phen为第二配体，通过水热法合成的配合物，其中，Co2+、Ni2+、Cu2+为中心离子；配合物3中的二价钴离子具有相同的配位环境，不同反应条件下得到的配合物4中的二价钴离子存在不同的配位环境，在配合物4中，一维链通过H4btc上的羧基形成一个二维层结构；配合物5、6是借助H4btc上的羧基形成的一维链状结构；配合物7、8属于异质同晶结构，它们的分子通过分子间氢键形成三维网状结构，H4btc上的羧基失去2个质子，作为一个二价负离子起到电荷平衡作用。

The results showed that: at metaphase I, the homoeologous chromosome pairing among different F1 hybrids ranged from 2.0 to 11.4 bi-valents formed by homoeologous chromosomes per pollen mother cell, and very few multivalents, and even very few bivalents were formed by two chromosomes within one genome rather than homoeologous chromosomes in some PMCs; at anaphase I, all biva-lents were disjoined and most univalents were divided.

结果表明在中期I阶段，这些杂种一代的近缘染色体联会变化很大，每个花粉母细胞中二价体形成的数目从平均2个到11.4个不等，甚至在某些花粉母细胞中，还发现极少的多价体和非部分同源染色体所形成的单基因组内二价体；在后期I时，所有的二价体分离，同时多数单价体也分离，分离的二价体和分离的单价体都移向两极，从而形成两组染色体；因为这时完整花粉母细胞中分离的二价体在两组染色体中总是对应出现，从而根据半二价体上染色体重组的位置可以分析在二价体的四分体时期发生在非姊妹染色体之间的多种染色体交换类型，如单交换、三线双交换、四线双交换、四线三交换和四线多交换。

In meiosis of pollen mother cells of the tetraploids and the hexaploids, only bivalents were observed in most of the populations, although in several populations or individuals a few univalents or tetravalents appeared. In the hexaploids, hexavalents were not observed.

四倍体和六倍体的花粉母细胞减数分裂染色体构型在大多数居群都为二价体(四倍体中30个二价体，六倍体中45个二价体)，少数居群或是个体除二价体为主外还出现单价体和四价体，六倍体类型没有出现六价体构型。

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。