ha.

ha.的基本解释

abbr.

hectare 公顷

与ha.相关的网络例句 [注：此内容来源于网络，仅供参考]

Through designing of composition and structure of the bioactive graded coating,innerstress and its distribution in the coating were analyzed and calculated, the resultsshowed that when composition distribution coefficient n was 1.5, a reasonable stressdistribution could be got, that was at the beginning of deposition the suspension containingrichly BG granules was used so that a rich BG granules layer, a good transitional layerbetween BG layer at the bottom and the coating could be obtained at the titanium alloy side,the bottom of the coating; the stress value near the interface and surface and its character,pressure stress or tensile stress, were decided by the character of its composition itself.Changing composition distribution coefficient n could only change the variation tendency ofstress in the coating, but did not change the stress distribution rule in the coating. Thethinner the coating is, the sharper stress variation in the coating is, which does not mean thatthicker coating is better because the thicker the coating is, the little the permitteddeformation of coating is, so the coating thickness should be thinner, for example, about50μm for bending applications, but for applications only bearing pure shear stress, such asroot of tooth implant, the coating can be thicker little, for instance, about 80～100μm. The study on electrification characteristic and electrophoresis deposition of HAand BG granules in aqueous and non-aqueous solution system found that EPD almost didn'toccur in aqueous solution system. However, because HA granules take position charges inabsolute alcohol, a homogeneous EPD be carried out on the cathode titanium alloy slice, but taking negative charge in absolute alcohol the BG granules not be deposited on the cathode. A guided HA crystallizing, 100～300nm, on surface of the BG granules be realized by metathetical reaction, which cover BG granules with HA microcrystals and make the covered BG granules taking position charges in absolute alcohol, sequentially realize the EPCD of the BG and HA granules on the cathode, so it is feasible to make a titanium alloy/BG/HA bioactive graded coating by making use of EPCD technology. The corrosion experiment of rich boron bioglass coating and plasma spray coating showed that split phase, rich boron and rich silicon phase, occurred during its preparation. In basic medium the corrosion behavior of 〓 BG coating showed uniformity corrosion, the corrosion mostly occurred at rich boron phase area, therefore batch formula design of BGshould avoid the occurring of split phase. The corrosion appearance of plasma spray coatingappeared a non-uniform corrosion, mostly occurred at the edge of the laminated HA moltendrops, and emerged an accelerated corrosion tendency, which will easyly lead to corrosioncrackles extending to the interface and the happening of osmotic interfacial corrosion, thatmay be one of the major reasons leading to the coating cracking-off in the later period. Thetesting results of thermal expansion coefficient of 〓 and 〓BG showed the thermalexpansion coefficient of 〓 BG matched with that of titanium alloy better, and 〓 BG couldsinter with titanium alloy into densification enamel layer at low temperature (720℃).

将Ti6Al4V合金在1000℃下进行真空热处理会降低其力学性能，且合金内的V元素会向表面富集，因此，钛合金真空热处理和表面涂层的烧结温度不能过高，即应低于其相转变点；通过对生物活性梯度涂层的组成和结构的设计，分析和计算了梯度涂层内的应力大小和分布，结果表明：对于本研究，当成分分布系数n=1.5时，可以获得较合理的涂层力学性能，即在沉积开始时，采用富含BG颗粒的悬浮液，以便在钛合金侧获得同底层BG有良好过渡的富BG涂层；梯度涂层界面和表面的应力大小、性质由材料组成本身的性质决定，改变成分分布系数，只能改变涂层内应力变化的趋势；涂层的厚薄不影响涂层内的应力分布规律，但涂层越薄，涂层内的应力变化越快，但这并不意味着涂层越厚越好，因为涂层越厚，涂层允许的变形越小，对于应用于弯曲受力部位的涂层而言，涂层应薄一点为好(50μm)；而对于仅纯受剪切应力的部位，如牙根种植体，涂层可适当加厚(80～100μm)；通过对HA和BG颗粒在水溶液体系和非水溶液体系中的带电特性和电泳沉积的研究发现，它们在水溶液体系中很难发生电沉积；在无水乙醇溶液中，HA颗粒带正电，可在阴极钛合金片上发生均匀的电泳沉积，而BG颗粒则带负电荷；利用复分解反应法，可以制得100～300nm的HA，通过诱导HA在BG颗粒表面结晶，可对BG颗粒进行表面包覆，获得了被HA包覆的BG颗粒，改变了BG颗粒表面的带电特性，使BG和HA颗粒在无水乙醇中均带上正电荷，从而实现了HA和BG颗粒在阴极上的共沉积。

Study the bioactivity of the n-HA/PA66 composite and the effects it would be to body's metabolism of calcium and phosphorus ion in vivo.(3) Study the osteo-conductivity and the ability to repair bone defect of the porous n-HA/PA66 composite and the feasibility use it as the scaffold of bone tissue engineering. Objects and Methods as follows: 1.To evaluate the biocompatability of nano-hydroxyapatite crystals and polyamide composite (n-HA/PA66) with the L929 cells.To proceed the morphological observation and take pictures of L929 cells after 1d,2d,4d,and 7d of co-cultured with extract of n-HA/PA66 ,and direct contact with n-HA/PA66.To determine light absorbtion value of every hole under 500 nm with enzyme linked immunity instrument after 1 d,2 d,4 d,and 7 d of contact of n-HA/PA66 extract with L929 cells,and direct contact with n-HA/PA66.In the meanwhile calculate the relative multiplication rate of cells,and evaluate them by six degree tests for cytotoxicity. To investigate the acute and chronic toxic reaction on the whole body induced by the new nano-hydroapatite crystals and polyamide composite(n-HA/PA66)after implanting in vivo and its effects on partial constitution of animal organs after implanting in vivo,and evaluate the potential and degree of subcuticular stimulation reaction.

本实验主要由以下三部分组成：一、n-HA/PA66 复合材料在动物体内、体外的生物相容性及生物安全性评价二、n-HA/PA66 复合材料植入动物体内的生物活性及近期对机体钙、磷代谢影响的实验研究三、网孔 n-HA/PA66 复合材料作为支架修复兔桡骨节段缺损的动物实验研究主要研究目标及方法如下：参照 GB/T16886.5-1997-ISO 10993-5：1992《医疗器械生物学评价细胞毒性试验体外法》之评价标准和要求，采用规定的 L929 细胞(小鼠结缔组织成纤维细胞)，分别经直接接触和材料浸提液与细胞共培养等方式对 n-HA/PA66 复合材料进行细胞毒性测试，采用细胞形态观察法观察两种细胞各组在 24h、48h、72h、5 天后各时相点的细胞形态学变化，并在显微镜下照相，从而对细胞与材料的生物相容性进行定性评价；同时采用细胞生长抑制法，以酶标仪定量测定评价各组 1，2，4，7 天 L929 细胞的相对增殖率，以定量测定并判别材料对细胞的毒性程度。

In the second part of this thesis. The biological process of porons HA/bBMP composite repairing experimental defect in the dog femora and monkey mandibular were investigated by the qualitative and quantitative methods. The results showed that not only were the speed and time of new bone ingrowing into the bBMP/HA composite much quicker and earlier than that of implants of HA alone, but also the quantity of new bone ingrowth into bBMP/HA composite was much higher than that of HA alone. The bone ingrowth of bBMP/HA composite at higher rate within 3 weeks. In this study, bBMP/HA promoted more active new bone formation in bone marrow tissue than did HA alone. This reveals that BMP, brought into the bone marrow with HA as a carrier, accelerates osteogenesis or osteoinduction, providing sime bone marrow cells with more differentiative potential.

论文第二部分应用定性和定量的方法，较全面地研究了HA/bBMP复合人工骨在修复狗股骨和猴下颌骨实验性缺损中的生物学过程，研究发现，新骨组织长入HA/bBMP复合人工骨的时间和速度都较单纯HA早和快，而且新骨形成量也明显高于单纯HA，HA/bBMP在挂入后早期(3周)的成骨最为活跃，自体骨髓组织可为BMP提供敏感的靶细胞，增强BMP的骨诱导效果和HA/bBMP复合人工骨的骨修复能力。

与ha.相关的网络解释 [注：此内容来源于网络，仅供参考]

Ah-choo! Whoa! -Ha ha ha：啊-咻!哇! -哈哈哈

Oh, look at me. I'm going to touch the butt.|噢, 看我的. 我要去摸那个大屁股. | -Ah-choo! Whoa! -Ha ha ha!|-啊-咻!哇! -哈哈哈! | Oh, yeah? Let's see you get closer.|哦,耶? 你走近点让我们看看.

Yes. Ha-ha：我也刚想说 - 哈哈

- Cast Away. - Ha-ha.|- "荒岛余生" - 对 | - Yes. - Ha-ha.|- 我也刚想说 - 哈哈 | He told the Dutch captain his name was Raphael Serrano...|他告诉荷兰舰长自己叫拉斐尔.塞拉诺

MAN: Ha ha! What's she doing with that lunger：哈哈,她跟那个肺结核者在干什么

I'll take my oath on it.|我发誓 | MAN: Ha ha! What's she doing with that lunger?|哈哈,她跟那个肺结核者在干什么 | Ha ha!|哈哈