Study on the Acute Toxicity of Rare Earth Yttrium to Earthworms under the Stress of Leaching Agent Ammonium Sulfate

[目的]考察浸矿剂硫酸铵（NH4）2SO4胁迫下稀土离子钇的毒性研究。[方法]选择蚯蚓作为土壤生态环境污染指示生物,采用滤纸接触法研究硫酸铵胁迫下稀土钇（ Y）对蚯蚓的急性毒性效应。[结果]①稀土钇单一染毒,蚯蚓的48 h 半致死率浓度为 LC50=213.41 mg/L、24 h半致死率浓度为 LC50=322.63 mg/L。②硫酸铵单一染毒下,蚯蚓的48 h半致死率浓度为 LC50=13.89 g/L、24 h半致死率浓度为LC50=15.05 g/L。③低浓度10 g/L的硫酸铵与稀土钇复合染毒,蚯蚓的48 h半致死率浓度LC50=198.65 g/L、24 h 半致死率浓度 LC50=399.85 g/L;中浓度14 g/L的硫酸铵与稀土钇复合染毒,蚯蚓的48 h半致死率浓度 LC50=167.3 mg/L、24 h半致死率浓度 LC50=256.73 mg/L;高浓度20 g/L的硫酸铵与稀土钇复合染毒,蚯蚓的48 h半致死率浓度 LC50=31.03 mg/L、24 h的LC50=127.65 mg/L。[结论]低浓度的硫酸铵降低稀土钇对蚯蚓的毒性,产生一定的拮抗作用。中浓度的硫酸铵增加稀土钇对蚯蚓的毒性,产生较明显的协同作用。高浓度硫酸铵显著增加了稀土钇对蚯蚓的毒性。稀土钇染毒下蚯蚓死体更易断裂,而活体对针刺反应相对不灵敏。     

电沉积钇对PAN基炭纤维的催化石墨化

在硝酸钇的乙醇溶液中将钇电沉积于PAN基炭纤维上,采用扫描电子显微镜对炭纤维表面电沉积钇的表面形貌进行了观察.通过钇的电沉积电量来调节钇在PAN基炭纤维表面的担载量,采用X射线衍射分析仪考察了不同钇担载量对不同热处理温度下PAN基炭纤维的催化石墨化效果,通过Scherrer和Bragg方程分别计算了石墨表观微晶尺寸(Lc)和(002)面的层间距(d002).结果表明,钇电沉积层对PAN基炭纤维具有明显的催化石墨化作用,在钇担载量为20%、热处理温度为2 400℃时,层间距d002值最小,为3.362,相应的石墨化度为90%.钇对PAN基炭纤维的催化石墨化机理遵循碳化物分解和碳的熔解析出机理.     

钇铝石榴石中三价镨离子谱的晶场分析

对Ｐｒ３＋：ＹＡＧ（钇铝石榴石）的晶场谱按Ｄ２对称，用中间耦合，算符等价方法进行理论计算，确定其晶场参量为（ｃｍ－１）：Ｂ２０＝８０，Ｂ２２＝－６８，Ｂ４０＝－３０５，Ｂ４２＝３９０，Ｂ４４＝１２００，Ｂ６０＝６０，Ｂ６２＝－１８６，Ｂ６４＝１０８２，Ｂ６＝－１７００。计算的晶场能级与实验吻合。     

Yttrium oxide (Y2O3) as an inert marker in digestibility studies with dogs, blue foxes and mink fed diets containing different protein sources

The study evaluated the use of yttrium oxide (Y(2)O(3)) as an inert marker in studies of apparent total tract digestibility in dogs, blue foxes and mink. Comparison was made with total faecal collection, and use of chromic oxide (Cr(2)O(3)) as marker respectively. Four experimental diets were added 0.1 g/kg yttrium oxide and 10 g/kg chromic oxide and fed to four animals of each species. Faecal recovery of yttrium oxide was 94.4% (SEM +/- 1.0), and of chromic oxide 105.8% (SEM +/- 1.5). The digestibilities of dry matter, crude protein, crude fat, starch and total carbohydrates obtained by total collection and yttrium oxide as marker showed close similarity, and in most cases not significant differences, independent of species and diets. In dogs, overall digestibilities of main nutrients with chromic oxide as marker were not significantly different from overall means obtained with yttrium oxide (p > 0.05). Overall digestibility of dry matter, crude protein and total carbohydrates in blue foxes and mink was significantly higher with chromic oxide than with yttrium oxide (p < 0.05). In dogs and blue foxes, digestibilities of individual amino acids determined by use of yttrium oxide were not different from values obtained using total collection of faeces, both within diets and for overall mean (p > 0.05). Overall amino acid digestibilities in dogs determined with chromic oxide as marker were similar to corresponding figures for yttrium oxide, whereas use of chromic oxide resulted in significantly higher digestibilites for a number of amino acids compared with yttrium oxide in foxes and mink (p < 0.05). The digestibilities of most main nutrients and amino acids revealed no interaction between diet and method (p > 0.05). The study showed that yttrium oxide can be used in low concentration in the feed, and allows high accuracy of analyses and thereby precise digestibility determination. It is concluded that yttrium oxide is an alternative inert marker to chromic oxide in the studied species.     

稀土Y3+对铜绿微囊藻生长及其抗氧化酶活性的影响

为探讨钇(Y3+)质量浓度对铜绿微囊藻(Microcystis aeruginosa)的生长及其抗氧化酶含量变化的影响,以铜绿微囊藻FACHB912为试材,研究了不同质量浓度的外源稀土Y3+对藻细胞生长、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性、丙二醛(MDA)含量的影响.结果表明,低质...     

凡纳滨对虾对家蝇蛆粉的表观消化率

以氧化钇(Y2O3)为指示剂,按照"70%基础饲料+30%试验原料"的方法测定了初始体重(2.20±0.15)g凡纳滨对虾对家蝇蛆粉的表观消化率。试验结果显示,凡纳滨对虾对家蝇蛆粉干物质、粗蛋白、粗脂肪和能量的表观消化率分别为68.18%、83.34%、89.26%和75.38%。凡纳滨对虾对家蝇蛆粉总氨基酸的消化率为86.56%,氨基酸消化率的变化范围为80.74%~92.31%,其中组氨酸、精氨酸、异亮氨酸和脯氨酸的消化率均在90%以上。研究结果为评价家蝇蛆粉的营养价值及其在凡纳滨对虾饲料中的应用提供了参考和依据。     

黄颡鱼对蝇蛆粉的表观消化率的研究

试验以三氧化二钇(Y2O3)为外源指示剂,采用"70%基础饲料+30%试验原料"的方法配制试验饲料,测定了初始体质量约为3.15 g的黄颡鱼(Peltobagrus fulvidraco)对蝇蛆粉的表观消化率。试验鱼养殖于室内循环水系统中,投喂试验饲料2周后,采用滤网捞取法收集粪便。结果显示,黄颡鱼对蝇蛆粉干物质、粗蛋白、粗脂肪、能量和总磷的表观消化率分别为80.35%、91.08%、71.59%、78.19%和67.12%。黄颡鱼对总氨基酸的表观消化率为95.53%,其中对丝氨酸的消化率最低,为82.58%,其他氨基酸的消化率均高于90%。结果表明,黄颡鱼幼鱼对蝇蛆粉干物质、蛋白质和氨基酸具有较高的消化吸收能力,这为评价蝇蛆粉的营养价值及其作为蛋白源在黄颡鱼饲料中的应用提供了相应的依据和参考。     

Idiopathic haemarthrosis in eight horses

Objectives To review eight horses diagnosed with idiopathic haemarthrosis and to describe the intra‐articular use of yttrium‐90 (⁹⁰Y) and methylprednisolone acetate (MPA) in recurrent haemarthrosis cases. Design Retrospective case series. Method The medical records, diagnostic images, histopathology and outcome of all horses diagnosed with idiopathic haemarthrosis between 1998 and 2010 were reviewed. Results Four Thoroughbred racehorses with haemarthrosis of the antebrachiocarpal joint had severe acute lameness (median, grade 4) and marked joint effusion after high‐speed exercise. Another four horses (2 Thoroughbred racehorses, 1 Standardbred racehorse, 1 Warmblood) had haemarthrosis of the tarsocrural joint and presented with mild, intermittent lameness (median, grade 1) and marked, persistent joint effusion. Six of the eight horses had recurrent haemarthrosis prior to treatment. Radiographic and nuclear scintigraphic examinations did not identify bone pathology. Diagnostic arthroscopy (7 cases) identified grossly hypertrophied yellow/brown discoloured synovium. Synovial histopathology of these cases revealed chronic synovial hyperplasia with severe haemosiderosis and granulomatous inflammatory reaction of varying severity. All horses underwent rest, bandaging and phenylbutazone administration. Two horses had subtotal mechanical synovectomy, four horses had intra‐articular administration of ⁹⁰Y and MPA, and one horse underwent both treatments. Seven cases returned to their previous use (median time, 7 months). Haemarthrosis recurred in three horses, two of which had received the ⁹⁰Y and MPA treatment. Conclusion Idiopathic haemarthrosis should be considered a differential for acute and recurrent joint related lameness and effusion. Recurrence appears not uncommon and the use of intra‐articular ⁹⁰Y and MPA in conjunction with a conservative management treatment protocol warrants further evaluation.     

稀土元素钐和钇对小球藻生长的影响

通过实验室模拟培养试验,研究了稀土元素钐(Sm)和钇(Y)对小球藻(Chlorellaellipsoidea)生长的影响。结果表明,低浓度稀土元素在试验初期对小球藻的生长略有刺激作用,但随着处理浓度的提高和处理时间的延长,小球藻的生长繁殖明显受到抑制;当Y浓度达25mg·L-1、Sm浓度达45mg·L-1时,小球藻生长基本停止;Y对小球藻的毒性要较Sm略大。     

Comparison of yttrium and chromic oxides as inert dietary markers for the estimation of apparent digestibility coefficients in mirror carp Cyprinus carpio fed on diets containing soybean-, maize- and fish-derived proteins

The apparent digestibility coefficients (ADC) of protein, lipid and energy components within three selected plant protein by‐products, i.e. solvent‐extract soybean meal, full‐fat soybean meal and maize gluten meal were evaluated for mirror carp (Cyprinus carpio L.). In a series of feeding and digestibility experiments, the ingredients were incorporated at the rate of 50% within a basal diet formulation, at the expense of a high quality fish‐meal (LT94) source using both yttrium oxide, Y₂O₃ and chromic oxide, Cr₂O₃ as inert markers in test diets. The ADC of nutrients obtained from Cr₂O₃ closely matched those obtained from Y₂O₃. The ADC of protein were generally high, with >91% for both the fish‐meal reference diet and solvent‐extract soybean meal, 86% for full‐fat soybean meal and 79% for maize gluten meal. The ADC by yttrium oxide gave values of 75–90% for protein. Similarly close values were obtained for both markers with respect to lipid ADC (77–91% with chromic oxide and 74–89% with yttrium oxide). It was concluded that the use of Y₂O₃ as an inert marker in digestibility studies with carp ought to be suitable for carp following further validation. This should be considered in view of predicting the digestibility of feeds for this fish species before inclusion in practical diets.