碱性反应

Other methyl nucleophiles includingMeMgBr, MeCeCl2, MeTiCl3, Me3Al, Me3ZnMgCl, MeMnClwere tried, but in all these cases no detectable amount of exo-C8-methylated product was obtained. Although protecting C3-carbonyl as 1,3-dioxolanes could be achieved, the serious enolization of C8-carbonyl was still problematic. Converting C9-furan ring to α,β-butenolide did depress the enolization, but desired C8-methylation was completely replaced by migration of the double bond of the butenolide.

在本论文的早期阶段，主要着眼于解决二环[3.2.1]-C8-羰基加成甲基所遇到的C9-呋喃环差向异构化和C3与C8两个羰基之间化学选择性的问题：通过引入不同金属降低甲基试剂的碱性并没有取得甲基化的成功；通过不同的方法将C3-羰基掩蔽，但是C8-羰基的烯醇化依然无法抑制；虽然通过将呋喃环转化为α，β-不饱和-γ-丁内酯可以抑制烯醇化，但内酯环上的双键迁移又成了新的竞争反应。

This technique has two prominent problems: titanium"s burning loss and high temperature melt treatment (up 1873K). The author puts forward melting protective cover used by plant ash which can insulate air and enhance effect of heat preservation effectively. At the same time, the author chooses alkalinous magnesite for furnace lining which can avoid redox reaction between silicon oxide (SiO2) and titanium, improve fireproofness of furnace lining and decrease titanium"s burning loss ratio.

针对制备工艺的两个突出问题：Ti元素的烧损问题和高温熔体处理问题(1873K以上)，提出利用草木灰作为熔炼的覆盖剂，能有效地隔离空气，强化保温效果，同时选用碱性镁砂炉衬，提高了炉衬的耐火度，克服了酸性炉衬中SiO_2与Ti元素的氧化还原反应，降低了Ti元素的烧损率。

The biomechanical tests showed that two kinds of artificial bones had not significant difference on compressive strength and Young\'s modulus(P＞0.05),while the flexural strength of nano-nacre artificial bone was less than the control group(P＜0.05).3.The results of CCK-8 showed that the difference were not significant in each group,the proliferation of osteoblast reached the peak at the 5th day;7 days after being co-cultured,the total protein content of study group was higher than control group and blank group(P＜0.05),while the difference between control group and blank group was not significantP＞0.05The difference of alkaline phosphatase activities among three groups was not significant(P＞0.05The SEM view showed that osteoblast attached and grew well in two kinds of artificial bone.4.X-ray photography showed that two kinds of powder started to degrade in 2 weeks;this phenomenon became more appear in 4 weeks,nano-nacre powder degraded faster than micron-nacre powder,while the hole shadow was easy to be found;in 8 weeks,all the femoral holes recovered and returned to normal bone mineral density in all groups.Analysis of tetracycline fluorescent double marks in the hard tissue grinding slices indicated that new bone grew fastest around the bone defect area in study group,while most slowly in blank groupP＜0.05 SEM(scanning electron microscope observation showed that nano-nacre powder degraded more quickly.The same result can be found through the demineralized sections morphometric analysis,and both of the composite artificial bones made from those two kinds of nacre powder had the good connection with the adjacent tissue in rats body without apparent inflammatory response.5.X-ray photography showed that rabbit\'s bone defects healed faster in study group since NNAB implanted than in control group since MNAB implanted.At 24 weeks after operation,bone density in radial defects had nearly accessed to the normal area,while lower in control group,and turned up nonunion in blank group;The checking of BMD showed that results in study group were higher than those in control group at 8,16 and 24 week(P＜0.05), and the difference between the BMD values in study group at 24 week and those in blank group was not significant(P＞0.05).The gross specimens showed satisfactory histocompatibility both in study group and in control group,with bone tissue growing from two sides into the center of implanted materials; Normal slices in HE stain and hard tissue grinding slices in Stevenel\'s blue/Van Geison\'s picro-fuchsin stain showed that the bone growth tendency was better in study group than that in control group,and the medullary cavity had been penetrated to the implanted materials in study group at 24 week;Analysis of tetracycline fluorescent double marks in the hard tissue grinding slices indicated that new bone in both groups grew fastest 8 weeks after surgery,while slow down at 16 week.

纳米珍珠层/消旋聚乳酸复合人工骨与微米珍珠层/消旋聚乳酸复合人工骨分别与成骨细胞共培养后，其各时间点CCK-8法检测值与空白对照无显著差异(P＞0.05)，成骨细胞均在第5天达到增殖高峰期；培养7天后，实验组细胞蛋白含量高于对照组及空白组(P＜0.05)，后两者之间则无显著差异P＞0.05碱性磷酸酶活性在三组间均无显著差异(P＞0.05电镜下可见成骨细胞在两种人工骨上都有良好生长贴附能力。4.X-ray显示两种粉体在大鼠股骨骨洞植入第2周时都开始出现了降解，第4周时更为明显，纳米珍珠层粉较之微米珍珠层粉降解更快，而空白对照组骨洞阴影仍可见，至8周时，则所有组骨洞均己闭合修复，X-ray下已不可见原钻孔痕迹，恢复正常骨质密度；硬组织磨片四环素荧光双标记结果显示纳米珍珠层粉植入组较其余两组在骨缺损区周围新骨生长速度更快，空白组速度最慢P＜0.05电镜观察及常规脱钙切片亦可见到纳米粉体降解较快；由以上两种原材料制得的纳米珍珠层/消旋聚乳酸复合人工骨与微米珍珠层/消旋聚乳酸复合人工骨在大鼠体内均与周围组织结合良好，无明显炎症反应。5.X-ray显示纳米珍珠层/消旋聚乳酸复合人工骨植入兔桡骨缺损区后其骨愈合速度较对照组微米珍珠层/消旋聚乳酸复合人工骨植入的快，至植入术后24周，实验组骨缺损区接近正常骨密度，对照组骨缺损区密度较低，空白组则呈现骨不连状态；骨密度测量结果显示术后8周、16周、24周实验组的骨密度值高于对照组(P＜0.05，24周实验组的骨密度值与术前所测得的正常值无显著性差异P＞0.05动物取材大体所见均显示组织相容性良好，骨组织逐渐由植入材料两端向中央生长；常规切片HE染色及硬组织磨片Stevenel\'s blue/Van Geison\'s picro-fuchsin联合染色均可见实验组骨缺损区长势优于对照组，至术后24周，实验组骨髓腔与材料已呈相交通状；硬组织磨片荧光显微镜下观察，两组材料在术后8周处于骨生长最快速时期，16周时速度开始减慢，术后4、8、16周时实验组的新骨生长速度均较对照组的快

The reaction of 〓was studied in a basic solution with UV-spectra and a comp-licated mechanism which include the free radical OH was sug- gested.

第二部分研究了配合物〓在强碱性溶液中被双氧水氧化生成〓的动力学，提出了一个复杂的自由基反应历程。

As an intermediate for preparing vanillin derived from glyoxylic acid, 3, 4-dihydroxymandelic acid is synthesized based on condensation of catechol and glyoxylic acid in alkaline aqueous solution.

以邻苯二酚和乙醛酸为原料，在碱性条件下发生缩合反应，合成了3， 4-二羟基扁桃酸，此物质是多种香料和药物合成的重要中间体。

Based on the principle of ester hydrolyzation to ether in alkali condition, the process for preparation of dimethyl sulfide from sodium methyl sulfate residue was investigated.

根据酯在碱性条件下水解反应生成醚的原理，研究了以甲基硫酸钠废渣为原料制备二甲基硫醚的方法。

In the second section, with ketone and hydroxylamine hydrochloride as the starting materials, 3-aminopropanol is prepared via three steps including reaction of ketone and hydroxylamine hydrochloride , condensation of ketoxime and acrylonitrile, and hydrogenation cracking of condensation product.

第二是3-氨基丙醇的制备，由酮肟丙烯睛缩合物催化氢化裂解制得：即先以酮、盐酸羟胺为起始原料在碱性条件下合成酮肟，再与丙烯腈反应生成酮肟丙烯腈缩合物后经催化氢化裂解制得3-氨基丙醇。

Results In define induction envioroment, HPMSCS can diferentiate into lipoblast、after 2 weeks, the induced cells are full of lipid droplet;HPMSCS can differentiate into osteoblasts, after 4 weeks, we can see calcified tubercle in the cells, calcium in the calcified tubercle can be dyed black by Von Kossa and ALP dying is positive reaction above 95%.

结果 HPMSCS在培养基中持续培养后，在特定诱导环境下，成功使其向成脂肪细胞转化，培养2周时，可见融合成团的脂滴充满整个细胞；成功使其向成骨细胞转化，培养4周以上可见明显钙化结节，von Kossa染色可将骨结节中沉积的钙染成黑色，碱性磷酸酶染色呈强阳性反应达到95%以上。

Under alkaline conditions, carboxymethyl konjac glucomannan with different degree of substitution was prepared through reaction of monochloroacetic acid and konjac glucomannan using isopropyl alcohol as dispersing agent.

以异丙醇为分散剂，在碱性介质中一氯乙酸和魔芋葡甘聚糖反应制备了系列羧甲基魔芋葡甘聚糖。

In addition of cytomorphologic identification, immunolhistochemic technique of bone morphogenic protein-monoclonal antibody, alkaline Phosphatase staining and concentration assays, as well as osteoblasts reaction to PTH-cAMP were used, according to the biologic character of osteoblasts.

除了在细胞形态学上对其鉴定外，还根据成骨细胞的生物学特性，首次引用了骨形成蛋白单克隆抗体免疫细胞化学技术，以及碱性磷酸酶染色和含量测定，成骨细胞对甲状旁腺激素-cAMP反应等方法，验证了经酶消化分离培养的兔颅骨细胞具有成骨细胞的功能和特性。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。