| 查看: 1188 | 回复: 8 | |||
| 本帖产生 1 个 翻译EPI ，点击这里进行查看 | |||
| 当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖 | |||
[交流]
求翻译 各位兄弟姐妹谢谢啦
|
|||
|
While we were not the ?rst to coin the term hydroxyalu-minosilicate (HAS), we were the ?rst to demonstrate that the formation of HAS limited the biological availability of aluminum (1). We have since strived to understand as much as we can about the inorganic chemistry of HAS and their role in the biogeochemical cycle of aluminum (2, 3)and through our efforts we have provided a full description of one of the very few examples of the chemistry of silicic acid (4). The latter, in undersaturated solutions (<2.0 mmol/L) at pH below ca 10 is a neutral monomer of which the only known chemistry is (i) with ammonium molybdate to form the Keggin-like molybdosilicic acid complex (the basis for the spectrophotometric measurement of silicic acid) and (ii) with aluminum hydroxide to form HAS. The latter has been shown by us to proceed by a competitive condensation reaction at an hydroxyaluminum surface (4). In a recent paper in Environmental Science & Technology (5) the authors have used the term HAS but they have ascribed their role in limiting the biological availability of aluminum to an alternative reaction pathway involving the reaction of aluminum with polysilicic acids. Many metal cations are chelated by poly-silicic acids (6) and the chemistry is completely different from that of the formation of HAS. The authors should recognize that using the term HAS to describe the products of the reaction of aluminum with polymeric silicic acids is potentially confusing and misleading. In the same paper evidence is presented to support the detoxi?cation of aluminum in the digestive gland in snails by its intralysosomal binding by polymeric silicic acid. The suggestion seems to be that freshwater snails are natural biosilici?ers, capturing silicic acid and concentrating it in lysosomes prior to its deposition as amorphous silica. That freshwater snails deposit amorphous silica is an intriguing suggestion but not one, to my knowledge, that has been supported by experiment or observation. In addition, for such a mechanism to account for the detoxi?cation of aluminum there would need to be a further mechanism for the uptake of aluminum into lysosomes which were actively scavenging and concentrating silicic acid. Again, Occam’s razor would suggest that no such mechanism exists. The limited support provided for such a mechanism in this paper is analyses of a single inorganic particle isolated from a digestive gland of a snail exposed to aluminum. The analyses are qualitative and distinct from other similar analyses published by members of the same research group (7–9)in that there is no evidence of any sulfur. Energy dispersive X-ray spectrometry (EDX) suggested an excess of silicon over aluminum while electron energy loss spectrometry (EELS) showed some similarity with synthetic protoimogolite. There is a simple explanation for this observation. The aggregate in question is a phytolith (amorphous silica of plant/algal origin) which probably originated from the diet of the snail, and upon which are adsorbed HAS. The latter, since aluminum was present in excess of silicic acid in the culture solution, was probably HASA (or protoimogolite) in which the ratio of Si:Al would be ca 0.5 (10), an observation supported by EELS, and could have formed either in the external solution or, conceivably at least, in the digestive gland itself. I am at odds to understand why the authors have chosen to expound a mechanism of detoxi?cation of aluminum in the snail for which there is not, as yet, any scienti?c basis. The authors have shown quite clearly that aluminum is a neurotoxin in the snail and that the toxicity can be alleviated by silicic acid. Upon the basis of the science to-date the mechanism of amelioration is likely to be the same as that described in other biota, which is through the formation of HAS. [ Last edited by syy311 on 2011-3-21 at 16:44 ] |
回复此楼» 猜你喜欢
0817 化学工程 299分求调剂 有科研经历 有二区文章
已经有4人回复
-
0854可跨调剂，一作一项核心论文五项专利，省、国级证书40+数一英一287
已经有5人回复
-
070300化学319求调剂
已经有6人回复
-
一志愿985，本科211，0817化学工程与技术319求调剂
已经有6人回复
-
一志愿西南交大，求调剂
已经有3人回复
-
286求调剂
已经有6人回复
-
焦虑
已经有11人回复
-
331求调剂（0703有机化学
已经有7人回复
-
298-一志愿中国农业大学-求调剂
已经有5人回复
-
297求调剂
已经有5人回复
» 抢金币啦！回帖就可以得到:
-
坐标上海，诚征女友，非常 着急，私信必回
+1/469
-
绍兴大学博士教师招聘1位（化学化工相关）
+5/345
-
电力全国重点实验室双一流A类长江学者团队招2026年全日制博士1名（4月3日截止）
+2/110
-
专业技术开发及第三方检测
+1/87
-
温州大学吕晶晶课题组2026年招生
+1/81
-
福建师范大学招收2026年化学、材料硕士3-4名
+1/80
-
愿遇见你，遇见不止擦肩而过的缘分
+1/76
-
西北工业大学光子学研究团队诚聘博士后！
+2/38
-
南京理工大学优青团队招聘副教授、博士后、博士、硕士生（化学、催化方向）
+1/35
-
中科院生态环境研究中心国重实验室招聘客座研究生1-2名
+1/31
-
南昌航空大学代威力教授招收光催化和光热催化研究方向博士生
+1/9
-
浙江大学高纯分离团队诚聘博士后
+1/8
-
华中科技大学管理学院招聘社会用工（科研助理）1名
+1/6
-
上海第二工业大学-朱大海课题组招生（过线就能调剂）
+1/5
-
南方科技大学生命科学学院基础免疫与微生物学系招收博士后
+1/4
-
深圳大学蔡兴科课题组博士后及研究助理招聘
+1/2
-
Top-88悉尼科技大学数据科学/AI 招收2027年入学 校奖 博士生1到2名(国际和本地学生）
+1/2
-
中科院杭州医学所金程组招聘核酸化学、药学、医学方向 博士后/科研助理
+1/2
-
香港科技大学（广州） 招收温室气体监测与减排方向的博士、博后、硕士、RA
+1/1
-
西安建筑科技大学冶金学院先进储能材料团队2026年招收调剂研究生
+1/1
3楼2011-03-21 17:55:25
syy311(金币+2, 翻译EPI+1): 继续努力哦 后续跟上啊，谢谢哦 2011-03-21 19:33:58
|
While we were not the ?rst to coin the term hydroxyalu-minosilicate (HAS), we were the ?rst to demonstrate that the formation of HAS limited the biological availability of aluminum (1). We have since strived to understand as much as we can about the inorganic chemistry of HAS and their role in the biogeochemical cycle of aluminum (2, 3)and through our efforts we have provided a full description of one of the very few examples of the chemistry of silicic acid (4). 尽管我们不是第一个给出HAS的定义的，但是我们确是最先阐明HAS限制铝的生物学效应的机制的。我们尽力去了解关于HAS的无机化学特性以及他们在铝的生化循环中的重要作用。经过努力，我们发现了硅酸化学这个非常罕见的例子并能够对其进行完整的描述。 |
2楼2011-03-21 17:54:17
4楼2011-03-21 17:58:55
5楼2011-03-21 19:32:39
