几种类固醇激素对真骨鱼免疫功能的影响

从神经内分泌免疫网络的角度阐述了皮质激素、雄激素、雌激素等几种类固醇激素对真骨鱼类免疫组织细胞及抗体产生的抑制作用和促进作用，从受体水平探讨了作用的机制，为鱼类神经内分泌免疫网络研究提供了较为丰富的资料和有益的思考。     

几种类固醇激素对真骨鱼免疫功能的影响

从神经内分泌免疫网络的角度阐述了皮质激素、雄激素、雌激素等几种类固醇激素对真骨鱼类免疫组织细胞及抗体产生的抑制作用和促进作用,从受体水平探讨了作用的机制.为鱼类神经内分泌免疫网络研究提供了较为丰富的资料和有益的思考     

锌液流速对Fe-B合金耐锌液冲蚀性能的影响简

采用圆盘旋转技术,研究了锌液流速对Fe-B合金耐锌液冲蚀性能和冲蚀界面形貌的影响。在锌液温度和冲蚀角度一定时,随锌液冲蚀速度的增加,与316L不锈钢相比,Fe-3．5B （质量分数,％）合金的冲刷腐蚀率呈现较为缓慢的线性增加趋势,表现出低的锌液冲蚀率。在较低的锌液冲蚀速度下,Fe-B合金的冲蚀率仅为316L不锈钢的1/3,传质过程主要通过锌液在Fe2 B网状间隙中的物理流动而进行;而在较高的锌液冲蚀速度下,Fe-B合金的冲蚀率远低于不锈钢,表现出更优异的抗锌液冲蚀性能,此时的传质方式主要是铁、锌原子在界面前沿直接的扩散反应。界面形貌分析表明,Fe-B合金良好的抗锌液冲蚀性能得益于冲蚀初期基体快速腐蚀所产生的界面前沿裸露、密集Fe2 B抗蚀骨架对流动锌液良好的隔离、阻挡效应。     

锌对高炉软熔带性能及滴落带锌收入量的影响

采用醋酸锌水溶液浸泡法制备了不同锌含量的综合炉料(65%烧结矿+21%球团矿+14%块矿),通过初渣形成实验及对滴落物的化学分析,研究了有害元素锌对高炉初成渣形成过程的影响。结果表明,铁矿石中锌含量增高会导致滴落温度升高,软熔温度区间加宽,透气阻力指数增大,压差波动频繁,并且当炉料加锌量超过一定限度时,滴落初渣中(Zn)含量明显增大。这意味着,高炉锌负荷增加将导致软熔带变厚、透气性恶化以及压差不稳定,并且可能会加剧锌对高炉下部的破坏作用。     

缺锌胁迫对水稻叶绿体抗氧化系统的影响

采用营养液培养方式,设置0,1.0×10^-10和1.0×10^-6mol/L 3个锌处理水平,研究了缺锌胁迫对水稻叶绿体活性氧水平、膜脂过氧化、抗氧化剂含量及抗坏血酸（As A）-谷胱甘肽（GSH）循环系统中相关酶活性的影响.结果表明：1.0×10^-10mol/L锌处理下,水稻叶绿体中H2O2,O2.^-和丙二醛（MDA）的含量显著升高,表明缺锌造成了水稻叶绿体内的氧化胁迫;抗坏血酸含量在1.0×10^-10mol/L锌水平上达到最高,而谷胱甘肽含量随缺锌程度的增加呈递减趋势;超氧化物歧化酶、抗坏血酸过氧化物酶、谷胱甘肽还原酶及单脱氢抗坏血酸还原酶等As A-GSH循环中的关键酶活性均于潜在缺锌（1.0×10^-10mol/L锌）下达到最大值,而在严重缺锌（0 mol/L锌）下又显著下降.研究表明：一定程度上缺锌可诱导水稻叶绿体内As A-GSH循环系统中的抗氧化剂水平和抗氧化酶活性增加,以减少活性氧的产生与膜脂过氧化的作用;但严重缺锌条件下水稻叶绿体中氧化胁迫突破了抗氧化保护系统的保护能力,使水稻受到伤害.     

等离子体辅助化学气相沉积法生长ZnO薄膜的研究

讨论了在不同基板温度下用等离子体辅助化学气相沉积法生长ZnO薄膜,用X射线衍射(XRD)分析仪、反射式高能电子衍射(RHEED)仪及X射线光电子能谱(XPS)分析ZnO薄膜的特征.分析结果显示,在基板温度为300 ℃,二乙基锌(DEZ)流量为50 mL/min条件下可得到优取向高晶化的ZnO薄膜.光学性能分析表明,ZnO薄膜是透明的,在可视区峰值透光率高达85%.     

施锌对薄壳山核桃幼苗生长及体内锌分配的影响

以薄壳山核桃1年生实生苗为材料,研究了施锌对薄壳山核桃幼苗生长的影响及锌元素在植株各器官中的分配规律。结果表明:叶面喷施低质量分数ZnSO4促进了薄壳山核桃幼苗的生长,ZnSO4质量分数过高时幼苗的生长反而受到抑制;用ZnSO4浸种也表现出"低促高抑"的效应;两种施锌方式下,随着ZnSO4质量分数的升高,叶片叶绿素含量均呈现出"下降—增加—迅速下降"的趋势;经叶面喷施后锌在薄壳山核桃各器官中的比例大幅增加,其中以叶片富集锌的量最多,茎次之,根系最少;而ZnSO4浸种后,以茎中锌积累的量最多,叶片次之,根系最少。综合试验结果认为,以0.4%ZnSO4叶面喷施对促进薄壳山核桃幼苗营养生长及光合作用效果最佳。     

Effects of ultradry storage on fluidity of plasma membrane of seed

The effects of ultradry seed storage on the fluidity of plasma membrane have been investigated using the DPH fluorescent probe (1, 6-diphenyi-1, 3, 5,-hexatriene). The results demonstrated that the micro-viscosity of plasma membrane of ultradried seeds has no significant changes compared with the seeds which were stored under - 20℃ condition. However, there is a little adverse effect on the seeds with extreme dehydration. The results were consistent with higher vigor level of ultradried seed. It indicated that ultradry seed storage could maintain the physiological function of seed, protect the integrity of the membrane and improve the storability of seed. Furthermore, the results also revealed that sugar has the effect on protecting membrane structure and preserving the fluidity of the plasma membrane under seed dehydration. In the meantime, some mechanism about ultradry seed storage and the tolerance of dehydration of seed have been discussed.     

不同水平蛋氨酸锌对羔羊增重的影响

选用3月龄羔羊80只,随机分为4组,在基础日粮中加3个水平剂量的蛋氨酸锌0.2、0.4、0.6 g/(只.日)饲喂50 d,观察蛋氨酸锌对羔羊增重及生长发育的影响。试验表明:蛋氨酸锌的添加水平为0.2 g/(只.日)时,育肥羔羊的增重、日增重、料肉比、钙、磷、粗蛋白的表观消化率最高,即羔羊饲料中0.2 g/(只.日)剂量的蛋氨酸锌,可使育肥羔羊得到最佳的生长效果。     

冲蚀角度对Fe-2.5B耐锌液腐蚀性能的影响

将试样装夹在自制的预设一定冲蚀角度的转盘上进行锌液冲蚀试验,实现流动锌液对试样冲蚀表面0°、30°、60°和90°冲蚀角下的冲刷腐蚀。结果表明:在圆盘转速为70r/min,冲蚀时间为24h的条件下,Fe-2.5B合金(质量分数,%)的冲蚀率随冲蚀角度的增加而逐渐降低,并在高角度下呈现急剧降低的趋势;而316L不锈钢的冲蚀率在冲蚀角为30°时最大,冲蚀角为90°时最小,表现出典型韧性材料的冲蚀率特性。Fe-2.5B合金在流动锌液中的冲蚀率仅为316L不锈钢的33%~38%,其优异耐锌液冲蚀性能依赖于Fe-B合金中网状Fe2B相对流动锌液的阻挡效应。同时,一定韧性相基体的存在对Fe2B在冲蚀过程中起到支撑作用,进而表现出该合金中两相结构在锌液冲蚀中的"腐蚀协同效应"。此外,冲蚀角度的增加造成锌液流速在试样表面的切向冲刷分量弱化而法向冲击分量强化,这使得冲刷对最外层疏松ζ-FeZn13相的移除作用减弱。强的传质过程随冲蚀角度的增加不断弱化,从而使网络状组织结构的Fe-B合金在锌液中的冲蚀率明显降低。     

UK pharmaceuticals: a matter of Life

A British anti-abortion organization, Life, has challenged the legality of an abortion clinic's prescribing of post-coital hormone treatment (PCHT), the so-called "morning-after pill." Life contends that, contrary to its classification by the Department of Health and Social Security, PCHT is an abortifacient rather than a contraceptive. Even if Life wins the case, successful prosecution of the abortion clinic appears unlikely because British law would require proof of intention to procure miscarriage.     

合成参数对MOCVD法生长氧化锌纳米针的影响

使用脉冲液滴注入式MOCVD,在金膜裹覆的MgO(100)衬底上于500℃合成氧化锌纳米针.纳米针为晶态并且在XRD谱线上主要呈现ZnO的4个衍射强峰(100)、(002)、(101)及(004).金没有起到催化剂的作用,在较薄(2.4nm)金膜上生长的纳米针密度较高且直径较小.500℃是ZnO纳米针较佳的合成温度,在温度不低于550℃时合成的是片状ZnO.每周期前驱体的注入剂量对纳米针的形貌有显著影响.充足的注入剂量(6.8mg/周期)能够保证纳米针合成,而较低的注入剂量(3.4mg/周期)将会合成较短且直径较小的纳米针.     

间接光度法测定药物中的抗坏血酸

利用抗坏血酸对铁（ Ⅲ）２〔２（６甲基苯并噻唑） 偶氮〕５二乙氨基苯甲酸络合物的还原作用,建立了一个间接光度测定抗坏血酸的方法． 在ｐＨ５０ ～７０ 的ＨＡｃＮａＡｃ 的缓冲介质中, 络合物的最大吸收峰位于６３５ ｎｍ , 摩尔吸光系数达到２２ ×１０５Ｌ·ｍｏｌ－ １·ｃｍ －１ ． 抗坏血酸浓度在０ ～０６４ μｇ／ ｍＬ范围内与吸光度呈良好的线性关系． 方法适用于市售维生素Ｃ片剂和针剂中抗坏血酸的测定, 结果与碘量法测定结果一致     

矽卡岩型含锌铁矿回收锌试验

根据矽卡岩含锌铁矿的矿物组成，对其进行了回收锌的试验，提出先浮后磁流程，并对磨矿细度、石灰用量、硫酸铜用量和丁黄药用量进行了条件试验，得到了合格的锌精矿，为矿山回收锌提供了可行性依据。     

Effects of zinc on physiologic characterization and cadmium accumulation and chemical forms in different varieties of pepper

The effects of zinc(Zn) at different spray concentrations(0, 500, and 1 0001μmol L) on the plant growth, the activities of antioxidant enzymes chemical forms of cadmium(Cd), and the accumulation of Cd were studied and compared between two varieties, Shijichaotianjiao(SJCTJ) and Yanjiao425(YJ425) of pepper(Capsicum annuum L.) in Cd-contaminated soil(Cd 10 1mg kg). The activities of catalase(CAT) and peroxidase(POD) were generally enhanced by Zn. However, superoxide dismutase(SOD) decreased. Addition of Zn decreased the ethanol-extractable Cd, NaCl-extractable Cd, and acetic acid-extractable Cd in the fruit by 34.6%- 55.3%, 2.0%-17.7% and 0.4%-32.9%, and reduced the accumulation of Cd in fruit and plant total Cd by 12.8%- 68.6% and 9.0%-29.3% in both varieties, respectively.     

Al-Ti-C-B中间合金对高铝锌基合金组织和性能的影响

研究了Al-6.53Ti-0.3C-0.46B中间合金（Ti:C＞4:1）对高铝锌基合金的组织和性能的影响,结果表明,加入适量的中间合金可显著细化合金的显微组织,初生富铝α相从粗大的树枝晶转变为细小均匀等轴晶,等轴晶尺寸30~50 μm。砂型铸造条件下,合金的伸长率从1.7%提高到10.0%,拉伸强度在410 MPa左右。金属型铸造条件下, 合金的伸长率从1.0%提高到16.0%,拉伸强度约407 MPa。尽管组织显著细化,但拉伸强度并没有显著增加。高铝锌基合金组织细化的机理主要通过加入Al-Ti-C-B中间合金增加了异质形核质点。     

Treatment of zinc deficiency without zinc fortification

Zinc （Zn） deficiency in animals became of interest until the 1950s. In this paper, progresses in researches on physiology of Zn deficiency in animals, phytate effect on bioavailability of Zn, and role of phytase in healing Zn deficiency of animals were reviewed. Several studies demonstrated that Zn is recycled via the pancreas; the problem of Zn deficiency was controlled by Zn homeostasis. The endogenous secretion of Zn is considered as an important factor influencing Zn deficiency, and the critical molar ratio is 10. Phytate （inositol hexaphosphate） constituted up to 90% of the organically bound phosphorus in seeds. Great improvement has been made in recent years on isolating and measuring phytate, and its structure is clear. Phytate is considered to reduce Zn bioavailability in animal. Phytase is the enzyme that hydrolyzes phytate and is present in yeast, rye bran, wheat bran, barley, triticale, and many bacteria and fungi. Zinc nutrition and bioavailability can be enhanced by addition of phytase to animal feeds. Therefore, using phytase as supplements, the most prevalent Zn deficiency in animals may be effectively corrected without the mining and smelting of several tons of zinc daily needed to correct this deficiency by fortification worldwide.