34 resultados para HD6994.L4 N3


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针对污染地表水的特点,从辽河油田受石油污染的缓流河床底泥中筛选出一株能有效去除CODCr的微球菌(Micrococcussp.N3-9P),并对其进行了化学包埋法固定化.通过实验,确定了改进的聚乙烯醇-海藻酸钠共固定工艺配方(质量分数)聚乙烯醇10.5%,海藻酸钠0.5%,活性碳3%及微量生长素,优化了过程控制参数.地表水修复实验表明,96h后固定化颗粒对污染地表水中CODCr的去除率为70.9%,明显高于游离菌的33.6%.

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Sphere NH4Y1.9Eu0.1F7 nanoparticles were successfully synthesized by a hydrothermal method at 180 degrees C for 10 h. SEM and TEM images show the particles are spheres and have lots of hollows in them. The mean particle size is about 60 nm. The shape and size of the particles can be controlled by changing temperature and time of reactants. The luminescent property of the sample indicates that strong emission peaks of the Eu3+ ions are located at about 589 and 612 mm.

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A series of single-component cobalt salen complexes, N,N'-bis(salicylidene)-1,2phenylenediamino cobaltIII X(X = Cl (1a), Br (1b), NO3 (1c), CF3COO (1d), BF4 (le), and N3 (If)) (SalphCoX), were prepared for alternating copolymerization of carbon dioxide and propylene oxide(PO) under mild condition. The axial anion X group of the SalenphCoX played important role in tailoring the catalytic activity, polymeric/cyclic carbonate selectivity, as well as stereochemistry of carbonate unit sequence in the polymer chain. SalenphCoX with an electron-withdrawing axial X group (complex 1c) was an ideal catalyst for the copolymerization of CO2 and PO to selectively produce polycarbonate with similar to 99% carbonate linkage and over 81% head-to-tail structure.

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一种素食者食用的调和油是由富含饱和脂肪酸的油脂、富含单不饱和脂肪酸的油脂、富含N6系列多不饱和脂肪酸的油脂、富含N3系列多不饱和脂肪酸的油脂在10~60℃条件下调和而成,调和油中脂肪酸的重量百分含量为饱和脂肪酸25~30wt%,单不饱和脂肪酸33~39wt%,多不饱和脂肪酸33~39wt%,其中N6系列多不饱和脂肪酸29~33wt%,N3系列多不饱和脂肪酸wt5~8%,并且N3、N6系列不饱和脂肪酸重量比例为1:4~6。本发明具有价格低廉,营养均衡,脂肪酸比例协调,适合素食者食用的优点。

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The interaction of antitumor antibiotic, echinomycin (Echi) with guanine (Gua) was thoroughly investigated by adsorptive transfer stripping cyclic voltammetry, ultraviolet and visible adsorption spectra (UV/Vis) and Fourier-transform infrared spectroscopy (FTIR). Electrochemistry provided a simple tool for verifying the occurrence of interaction between Echi and Gua. Echi could be accumulated from the solution and give well-defined electrochemical signals in 0.1 M phosphate buffer solution (pH 7.0) only when Gua was present on the surface of the electrochemically pretreated glass carbon electrode (GCE), suggesting a strong binding of Echi to Gua. All the acquired spectral data showed that a new adduct between Echi and Gua was formed, and two pairs of adjacent intermolecular hydrogen bonds between the Ala backbone atoms in Echi and Gua (Ala-NH to Gua-N3 and Gua-NH2 to Ala-CO) played a dominating role in the interaction. Electrochemistry coupled with spectroscopy techniques could provide a relatively easy way to obtain useful insights into the molecular mechanism of drug-DNA interactions, which should be important in the development of new anticancer drugs with specific base recognition.

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Four new organotin complexes, namely [(Bu2Sn)(2)O(EtO)(L1)](2) (1), [(Bu2Sn)(2)O(EtO)(L2)](2) (2), [(Bu2Sn)(2)O(EtO)(L-3)](2) (3) and [Ph3Sn(L4)]center dot 0.5H(2)O (4), were obtained by reactions of Bu2SnO and Ph3SnOH with 4-phenylideneamino-3-methyl-1,2,4-triazole-5-thione (HL1), 4-furfuralideneamino-3-methyl-1,2,4-triazole-5-thione (HL2), 4-(2-thienylideneamino)-3-ethyl-1,2,4-triazole-5-thione (HL3) and 4-(3,5-di-t-butylsalicylideneamino)-3-ethyl-1,2,4-triazole-5-thione (HL4). Compounds 1-4 were characterized by elemental analysis, IR spectra and their structures were determined by single-crystal X-ray diffraction methods. Complexes 1-3 show similar structures containing a Sn4O4 ladder skeleton in which each of the exo tin atoms is bonded to the N atom of a corresponding thione-form deprotonated ligand. Complex 4 shows a mononuclear structure in which the tin atom of triphenyltin group is coordinated by the S atom of a thiol-form L4(-) anion.

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In this paper, four new luminescent silver(I) sulfonate complexes with PPh3, namely Ag(L1)(PPh3)(2) (1), Ag(L2)(PPh3)(3) (2), [Ag-2(L3)(PPh3)(4) (H2O)center dot 1.5CH(3)CN center dot 0.5H(2)O (3) and [Ag-4(L4)(PPh3)(10)]center dot 8H(2)O (4), where L1=p-toluenesulfonate, L2=1-naphthalenesulfonate, L3=3-carboxylate-4-hydroxybenzenesulfonate, L4=1, 3, 6, 8-pyrenetetrasulfonatc and PPh3=triphenylphosphine, have been synthesized and characterized. The crystal structures were determined by single-crystal X-ray diffraction method. Compounds 1, 2, 3 and 4 adopt discrete structures rather than polymeric structures. Compounds I and 2 show mononuclear structures while 3 and 4 are dinuclear and tetranuclear molecules, respectively. Moreover the numbers of PPh3 molecules coordinating to one silver center are two or three. The photoluminescent properties of 1, 2 and 3 are discussed.

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Oxochromium (V) tetraphenylporphyrin complexes, O = Cr (V) TPP (Cl) PhI. O = Cr-(V) TPP (N3) PhI and O = Cr (V)TPP (p-CH3OC6H4O)1/2PhI were isolated from the reaction of Cr (III) TPP (Cl). Cr (III) TPP (N3) Py or Cr (III) TPP (p-CH3OC6H4O) THF with iodosy

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对四种大型海藻:江篱(Gracilaria textorii)、孔石莼(Ulva pertusa)、海带苗(Laminaria japonica)和多管藻(Polysiphonia urceolata)表面附着弧菌的多样性进行了分析,同时对多样性分析中采用的不同方法进行了比较。 利用TCBS培养基从四种海藻表面总共分离到12株细菌:G1、G2分离自江篱,U3分离自孔石莼,L4、L5、L6分离自海带苗,P7、P8、P9、P10、P11、P12分离自多管藻。菌株G1,G2属于盐单胞菌(Halomonas),其余10株细菌都属于弧菌(Vibrio)。 对12株细菌的酶学活性、抗生素抗性进行了研究。发现除G1、G2外,其余菌株都可产生淀粉酶和明胶酶。菌株G1、G2和U3对氨苄青霉素、链霉素和四环素有很强抗性。 采用多种分子生物学方法(16S rDNA、gyrB、RFLP、DGGE )分析了上述12株菌的系统发育关系,对不同方法获得的结果进行了比较。 12株菌的16S rDNA系统发生树可分为4个明显分支。G1、G2与细菌H. meridiana构成一个分支。U3与V. lentus构成一个分支。L4、L5、L6、P9、P10、P11、P12与V. tasmaniesis形成一个分支。P7、P8与V. splendidus形成一个分支。 以gyrB基因序列为基础构建的系统发生树将G1、G2以外的10株弧菌分成4个较大分支,L4、P9属于同一分支,L6、P8、P10、P11和P12属于一个大的分支, U3、L5各自构成一个分支。菌株G1、G2没有得到gyrB基因序列扩增带。表明试验设计的引物是弧菌特异性引物。相对16S rDNA,不同菌株间gyrB基因序列差异性更大。 RFLP分析结果显示,12株细菌HinfI酶切后得到6种带型,SmaI酶切后得到4种带型。结合16S rDNA、gyrB基因的分析结果可知,RFLP可以在种的水平上有效进行细菌多样性分析。 12株细菌的DGGE分析结果显示,G1、G2与其它菌株电泳图谱有明显不同。菌株U3独自构成一种带型,L5、L6构成一种带型。表明DGGE技术在属的水平上分析细菌多样性效果较好,在种的水平上分析细菌多样性有一定的局限性。

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贝类养殖是我国海水养殖业中最重要的组成部分之一。贝类人工大规模养殖中的关键环节是种苗的人工繁育,早期幼虫能否正常生长发育,对幼虫变态和变态后生长率及成活率有很大的影响,直接关系到生产产量和经济效益,所以,了解幼虫发育机制对于生产实践具有重要的指导意义。 文蛤(Meretrix meretrix)是一种在东亚各国沿海和滩涂地区广泛分布的双壳贝类,是我国一种重要的经济品种。本论文以文蛤幼虫为研究对象,分别对文蛤幼虫发育过程中贝壳形成相关的铁蛋白(MmeFer)、营养及变态相关的组织蛋白酶B(MmeCB)及变态过程中细胞凋亡相关的caspase三个基因进行了克隆,分析了基因及编码蛋白在担轮幼虫期(L1)、D形幼虫期(L2)、壳顶幼虫期(L3)和稚贝期(L4)的时空表达特征,解析了其可能的功能,并研究了相应酶类的特异性抑制剂作用对幼虫发育过程的影响,进行了目标蛋白的功能验证,详述如下: 研究结果显示,在文蛤胚胎发育到原肠胚时放入不含铁离子的人工海水中培养,发育成无壳的畸形,随着人工海水中铁离子添加浓度的升高,幼虫长出壳状组织接近正常状态;而发育到L1期幼虫放入不含铁离子的人工海水中培养却可以发育出正常的壳,推测铁和铁代谢相关蛋白在幼虫贝壳初始形成有重要的作用。根据构建的文蛤幼虫cDNA文库中提供的序列信息,从文蛤中克隆了与铁离子代谢密切相关的铁蛋白(MmeFer)的全长cDNA 序列;通过Real time PCR发现,MmeFer mRNA的表达量在贝壳形成前后有明显改变;整体原位杂交结果显示MmeFer mRNA在L1期的表达部位刚好是贝壳生成的起始部位,推断文蛤铁蛋白与文蛤幼虫贝壳初始形成密切相关。 利用文蛤幼虫cDNA文库中的EST信息在幼虫中克隆到文蛤组织蛋白酶B(MmeCB)全长cDNA序列;通过整体原位杂交分析发现MmeCB mRNA在L2至L4期幼虫的消化腺部位表达,而且在L2期的幼虫表皮也有表达,说明MmeCB可能和幼虫消化相关,而且可能参与幼虫从表皮摄取营养的过程。利用MmeCB特异性抑制剂(CA074Me)处理饥饿幼虫,发现其生长受到明显抑制,验证了MmeCB参与幼虫表皮营养代谢的推论。利用免疫组织化学技术,研究了MmeCB蛋白在文蛤幼虫中的时空分布,发现其在L2期幼虫表面和胃部有阳性信号,而在L3期,MmeCB在幼虫面盘基部有强烈的表达,提示MmeCB在文蛤幼虫中不仅起到营养的作用,而且可能和幼虫附着变态有关。利用CA074Me分别处理文蛤胚胎和变态期幼虫,发现抑制MmeCB的活性对胚胎发育和幼虫变态都有显著影响。研究结果提示MmeCB在幼虫发育各阶段均具有重要的生物学功能。 根据caspase在不同物种中的保守区域设计简并引物,在文蛤幼虫中扩增到cDNA序列片段;检测有活性的caspase在文蛤幼虫各发育时期的分布部位,发现其在L1至L3期幼虫中都有分布,说明整个幼虫形态变化过程中都有caspase的参与;细胞凋亡检测结果显示,幼虫主要发生细胞凋亡的部位在L3期幼虫的面盘,即变态过程中要退化的器官,说明细胞凋亡可能是文蛤幼虫变态过程中面盘退化的主要机制;用caspase特异性抑制剂处理变态前幼虫,发现幼虫变态率下降,初步验证了caspase在文蛤幼虫变态过程中的作用。 通过对上述三种基因的研究,分别探讨了文蛤幼虫发育阶段中的几个主要事件(L1期到L2期的贝壳形成、L2到L3期的幼虫营养摄食及L3到L4期的附着变态)相关的基因及其功能,为研究贝类生长发育调控的分子机理提供了新的线索。

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本论文的研究工作由两部分组成,第一部分研究了海带(Laminaria japonica)水提取物中的活性物质,并研究了提取物对蔬菜促生长的影响及其作用机制。第二部分对三列凹顶藻(Laurencia tristicha)乙醇提取物的乙酸乙酯相进行了活性筛选和化学成分研究,并对其中分离得到的单体化合物进行了生物活性筛选。 第一部分主要以中国人工养殖的海带为原料,使用与海藻多糖生产相结合的提取技术并浓缩其中的有效成分。对浓缩提取物进行了蔬菜的农田效果实验,并对作物抗旱性能的增加、作物硝酸盐积累的减少、作物品质的改善、以及作物抵抗病毒病的能力等影响进行了作用机制方面的研究。海藻浓缩提取物进行的农田效果实验表明:作物抗旱型相对含水量RWC值在92%~94%之间;病毒病的防治效果最高可达到91%;作物的品质有明显的改善,最重要的是首次发现海藻提取物有降低蔬菜中硝酸盐的含量(硝酸盐的含量是与有机蔬菜区别的重要指标之一)的作用。该部分研究工作的创新性主要体现在:(1)首次在国内外提出和采用与海藻多糖生产相结合的提取技术。该技术的应用不但减少了提取成本,使工业化生产成为可能,更重要的是使我国的海藻工业生产可能实现高值化和开辟综合利用的新途径。(2)首次发现海藻中的小分子海藻多糖具有和细胞激动素、甜菜碱、植物生长素等活性物质同样的生物活性。 第二部分的研究是在查阅了大量的近20年来国内外有关红藻凹顶藻中化学成分研究的相关文献的基础上,对凹顶藻中的次生代谢产物进行了综述。该论文主要是通过对红藻三列凹顶藻的95%乙醇提取物的乙酸乙酯相进行化学成分分析和生物活性筛选以期能够发现具有药用前景的活性先导化合物。 为了寻找具有生物活性的化合物,我们对采自我国南海硇洲岛海域的红藻三列凹顶藻的95%乙醇提取物的乙酸乙酯相进行了活性筛选。采用MTT法对其在KB细胞株、Bel-7402细胞株、PC-3M细胞株、MCF-7细胞株、Ketr-3细胞株模型上进行了细胞毒活性测试;采用酶模型对其进行了Na+,K+-ATPase的抑制活性测试;采用MTT法对其在犬主动脉血管模型上进行了血管平滑肌细胞增殖抑制活性测试;结果表明,三列凹顶藻的95%乙醇提取物的乙酸乙酯相对Na+,K+-ATPase和犬血管平滑肌细胞增殖具有一定的抑制活性。 利用正相和反相色谱、Sephadex LH-20色谱以及反相HPLC等手段进行分离纯化,从我国南海海域的红藻三列凹顶藻中分离得到33种化学成分,通过波谱学方法(IR、MS、NMR)以及X-ray单晶衍射试验对其化学结构进行了确证,其中化合物L1~L8为新结构化合物,化合物L5为具有新骨架的全新结构化合物,化合物L9~L13为新天然产物,化合物L18和L22系首次从海洋生物中获得,所有化合物均为首次从该属海藻中得到。新化合物L1~L8均为倍半萜类化合物,命名分别为:(1R,3R)-(-)-3-(3-hydroxy-4-methylphenyl)- 1,3-dimethyl–2-methylidene cyclopentanol (L1), (1R,3R)-(-)-3-(4-methylphenyl)-1,3-dimethyl-2-methylidenecyclopentanol (L2), (1R, 3R)-(-)-3-(2-hydroxy-4-methylphenyl)-1,3-dimethyl–2–methylidenecyclopentanol (L3),(+)-(1S,2R)–2-(3–hydroxy–4–methylphenyl)-1,2-[3.1.0]bicy-clohexane (L4),()-(1S,2R) -5-hydroxy–6–methyl-spiro-dihydrobenzofuran-2(3H),2-{1-methyl-[3.1.0]bicyclohexane} (L5), (+)-6-methyl-2-(p-tolyl)hept-4-en-2,6-diol (L6),(3R,3aS,8bS)-(-)-2,3,3a,8b–tetrahydro–7-bromo – 3 a– hydroxymethyl - 3, 6, 8b - trimethyl-1H- cyclopenta[b] benzofuran (L7 ),(3R, 3aS, 8bS) - (-) - 2,3,3a,8b–tetrahydro–3 a–hydroxymethyl-3,6,8b -trimethyl -1H – cyclopenta [b] benzofuran (L8)。25个已知结构化合物确定为:(+)-(1R,2R)-4-bromo-1,5, 9–trimethyl–12– methylidene–8–oxa-tricyclo[7.2.1.02]dodeca-2,4,6-triene (L9),(3S,3aR,8bS)-(-)-2,3,3a, 8b– tetra -hydro–7-bromo–3–hydroxy-3,3a,6,8b-tetramethyl-1H-cyclopenta[b]benzofu- ran (L10 ),(3R, 3aR, 8bS) - (-) - 2, 3, 3a, 8b – tetrahydro – 7 - bromo – 3 – hydroxy - 3,3a,6,8b - tetramethyl - 1H - cyclopenta [b] benzofuran (L11 ),(3S,3aR,8bS) - (-) - 2, 3, 3a, 8b – tetrahydro –3–hydroxy -3, 3a, 6, 8b - tetramethyl-1H-cyclopenta[b]benzofuran (L12 ), ( 3aR, 8bS) - (-) - 3a,8b –dihydro–7 - bromo – 3, 3a, 6, 8b - tetramethyl - 1H - cyclopenta[b]benzofuran (L13 ),aplysinol (L14 ) ,aplysin (L15),laurebiphenyl (L16),johnstonol (L17),gossonorol (L18),7,10-epoxy-ar- bisabol-11-ol (L19),10-epi-7,10-epoxyarbisabol-11-ol (L20) 3β-hydroxy- 5α, 6α-epoxy- β- ionone (L21 ),3β-hydroxy-5β,6β-epoxy-β-ionone (L22 ),胆甾醇 (L23 ),胆甾-5-烯-3β,7α二醇胆甾-5-烯-3β,7α二醇 (L24),β-谷甾醇 (L25),叶绿醇 (L26 ),玉米黄素 (L27 ),对羟基苯甲醛 (L28 ),3-吲哚甲醛 (L29 ),1-O-十六烷酰基-3-O-β-D-吡喃半乳糖基-丙三醇(L30 ),1-O-十八烷酰基-3-O-β-D-吡喃半乳糖基-丙三醇 (L31 ),丙三醇-1-软脂酸单酯 (L32 ),正十六碳酸 (L33 )。 采用MTT法对其中23个单体化合物在Bel-7402细胞株、BGC-823细胞株、A549细胞株、A2780细胞株、HCT-8细胞株和HELL细胞株模型上进行了细胞毒活性测试;采用MTT法对其中13个单体化合物在犬主动脉血管模型上进行了血管平滑肌细胞增殖抑制活性测试;结果表明,部分单体化合物显示出一定的生物活性。

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2002年4月至8月,在中国科学院海北高寒草甸生态系统定位站附近,采用标志重捕法对高原鼠兔的繁殖特征进行了研究.高原鼠兔的繁殖具有明显的季节性差异,4月下旬和5月为繁殖高峰期,雄性的睾丸重而饱满,雌性的怀孕率最大.雄性成体的体重和睾丸重在繁殖期的不同时段具有显著的差异,在4月11日至5月10日、6月11日至7月10日体重和睾丸重之间呈显著正相关.雌性怀孕早期胚胎数与临产前胚胎数没有显著差异,未发现胚胎吸收现象;同时,胚胎数在繁殖期的不同时段存在显著差异.采用种群统计学中同生群的划分方法,将5~8月份出生的幼体依次记为L1、L2、L3、L4.在出生后20天内L1、L2幼体存活率明显高于L3、L4;在从出生50天至80天期间L1的存活率显著高于L2.当年出生的雌雄幼体在发育上存在不同步现象,当年出生的雌性幼体性成熟早,有的可以直接参加繁殖,但当年出生的雄性幼体却无此现象.结果表明:在海北地区,经过综合治理后,高原鼠兔的生境发生改变,其繁殖策略也随之发生改变,即,减少每次繁殖活动的投入,增加繁殖次数,延长繁殖时间.

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Linxia Basin, situated in the northeast belt of the Tibetan Plateau, is a late Cenozoic depression basin bounded by the Tibetan Plateau and the Chinese Loess Plateau. The Cenozoic deposition, spanning over 30Ma, in which very abundant mammal fossils were discovered, is very suitable for study of uplift processes and geo-morphological evolution of the Tibetan Plateau. The Longdan section (35°31′31.6″N,103°29′0.6″E) is famous for the middle Miocene Platybelodon fauna and the late Miocene Hipparion fauna for a long time and is also one of the earliest known places for wooly rhino, which lies on the east slope of Longdan, a small village of township Nalesi in the south of the Dongxiang Autonomous County, Linxia Hui Nationallity Autonomous Prefecture. The Longdan mammal fauna was discovered at the base of the Early Pleistocene loess deposits at Dongxiang, where the lithology is different from the typical Wucheng Loess on the Chinese Loess Plateau. The rich fossils contain many new species and the major two layers of fossils are in the loess beds. Geologically the fossiliferous area is located in the central part of the Linxia Cenozoic sedimentary basin. Tectonically the Linxia Basin is an intermountain fault basin, bordered by the Leijishan major fault in the south and the north Qinling and Qilianshan major faults in the north. The section is 51.6m thick above the gravel layer, including the 1.6m Late Pleistocene Malan Loess on the top and the other loess-paleosol sequences in the middle of the section. The base of the section is the Jishi Formation, consisting of gravel layer of 13 ~ 17m thick. In this study, 972 bulk samples were collected with an interval of 5cm and other 401 orientied samples were taken with a magnetic compass. In the laboratory, the paleomagnetism, medium grain size, susceptibility, color, micromorphology, anisotropy of magnetic susceptibility were analyzed. From the stratigraphic analysis, the Longdan section from the top 0.3m to the bottom 51.6m, containing 5 normal polarities (N1-N5) and 5 reversal polarities (R1-R5). The paleomagnetic results show N3 is the Olduvai subchron in the middle of the Matuyama chron, and then the chronology of the Longdan mammal fauna is constructed along the section. The Matuyama-Gauss boundary is 45m and N5 enters Gauss chron. The Olduvai subchron with the age of 1.77 ~ 1.95Ma is found just in the upper fossiliferous level of Longdan mammal fauna. Taking the deposit rate of the section into account, the geological age of the upper fossiliferous level of Longdan mammal fauna is estimated to be about 1.9Ma. The lower fossiliferous level is just below the Reunion subchron and its age is estimated to be 2.25Ma. In addition, anisotropy of magnetic susceptibility of the loess-paleosol and other climatic indexes were used for discussing the late Cenozoic paleoenvironmental changes at Longdan, from which the Longdan area should have been an area of predominantly steppe the same as the Longdan mammal fauna.

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根据岩石矿物学研究,包括岩石结构、橄榄石的Fa值和低钙辉石的Fs值以及金属模式含量等,100块格罗夫山陨石分别被划分为:4块H3型、11块H4型(其中一块为H4-an)、10块H5型、3块H6型、2块L3型、6块L4型、31块15型、32块L6型和1块LL4型。格罗夫山普通球粒陨石在类型分布上,其比例和南极以及非南极普通球粒陨石有显著不同,说明可能存在相当数量的成对陨石。分类陨石样品比较新鲜,其中98块陨石的风化程度为W1,仅有2块陨石风化程度分别为W2和W3。另外,这些陨石中冲击程度较高的样品占有一定比例,它们是研究冲击作用的理想样品。

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运用MINTEQ 化学平衡软件对巢湖、龙感湖中溶解态稀土的形态进行模拟。模拟结果表明, 在巢湖和龙感湖中Ln (CO3) 2- , LnCO3+ 是溶解态稀土的最主要的存在形式, 当8 > pH > 7. 19 时, REE 主要以LnCO3+ 形式存在, 当pH > 8 时, REE 主要以Ln (CO3) 2- 形式存在, 并且ΣLn (CO3) n3 - 2 n ( n = 1 和2) 形态的稀土基本上占溶解态稀土总含量的93 %以上。Ln3 + 在巢湖和龙感湖水体中平均丰度为5. 03 % , Ln3 + 的丰度和pH 值成反相关关系。LnPO4 在湖水中平均丰度为1. 61 % , 但这种形式的稀土在巢湖和龙感湖中非常重要。巢湖和龙感湖中LREE 的LnPO4 均处于过饱和状态, 甚至巢湖西半湖区丰水期HREE 的LnPO4 的也都处于过饱和状态, PO43 - 对稀土的存在有很强的限制作用。LnSO4 , LnF2 + , LnOH2 + , LnCl2 + 等形态的各元素平均丰度均小于1 % , 在富营养化的淡水中通常可以忽略不计。