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62例佝偻病患儿头发钙元素分析 总被引:2,自引:0,他引:2
为了解佝偻病患儿头发钙含量情况,将测得的62例佝偻病患儿发钙值进行了分析。结果表明,男女佝偻病患儿头发钙含量均高于正常值,其中男患儿头发钙与正常值相比,差异具有高度显著性意义(P<0.01);男女佝偻病患儿与体检儿头发钙比较,前者均高于后者,但无统计学意义;男女体检儿及男女佝偻病患儿之间头发钙含量差异无显著性。结果提示,佝偻病患儿发钙值并不比正常值低,相反还高于正常值,故不能简单地用发钙值高低来反映体内钙的营养状况。 相似文献
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第62届流变学学会年会于1990年10月21~25日在美国圣菲市举行。会议共发表学术论文171篇,内容涉及理论流变学、实验方法、加工流变学与数值方法、聚合物溶液与熔体、非线性及大变形响应等共30个专 相似文献
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A molecular electronegativity distance vector based on 13 atomic types (MEDV-13) is used to describe the structures of 62 polychlorinated naphthalene (PCN) congeners and related to the gas chromatographic relative retention indices (RIs) of PCNs. Using multiple linear regression,a 4-variable quantitative structure-retention relationship (QSRR) with the correlation coefficient of estimations(r) being 0.9912 and the root mean square error of estimations (RMSEE) being 31.4 and the correlation coefficient of prediction (q) and the root mean square error of predictions (RMSEP) in the leave-one-out procedure are 0.9898 and 33.76,respectively. 相似文献
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贵刊1994年第6期所载《化学规律与特殊62例》一文,读后觉得,对于高考复习教学,帮助学生总结一些小规律,并注意其特殊情况,很有稗益。 相似文献
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用INDO法研究了C62O3的结构与光谱,结果表明,C62O3有C20和C5两种种稳定构型,其中C20构型能量较低。利用C60的碎片拓扑图讨论基加成及环加成产物对称性的规律,理论计算与^13CNMR谱的实验结果相符合。 相似文献
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CMC-Na/DETA-B62型蛇笼树脂对金属离子的吸附性能 总被引:1,自引:0,他引:1
本文研究了自合成的蛇笼型螯合树脂-二乙烯三胺交联甘油环氧树脂/羰甲基纤维素体系对Cd^2 ,Pb^2 ,Fe^2 的吸附量,吸附动力学,等温吸附过程等静态吸附性能,同时研究了pH值等因素对吸附性能的影响。实验结果表明,该树脂对Cd^2 具有较强的吸附选择性,能在Cd^2 ,Pb^2 ,Fe^2 3种离子共存时选择吸附Cd^2 ,其选择性系数分别为Kcd^2 /pb^2 =3.77,Kcd^2 /Fe^2 =9.61。该树脂对上述3种离子的吸附量可分别达4.00,1.06,0.42mmol/g。该类树脂可用于含重金属离子污水的处理和金属离子的分离等方面。 相似文献
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Experimental data existing in the literature on broadening and shift at low densities and on position of the red satellite band of the D1 line of Cs perturbed by Xe are used to obtain information on the range 6Å-∞ of the difference potential. Assuming a Lennard-Jones (n-6) model, best agreement is obtained for n=8 and n=7, in accordance with the low curvature expected for a secondary well. Potential for the first excited state is obtained by addition of the difference potential to the ground state potential, and the parameters of the resulting secondary well are given. 相似文献
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Jun Zhou Prof. Sha Yang Yesen Tan Huaisheng Cheng Dr. Jinsong Chai Prof. Manzhou Zhu 《化学:亚洲杂志》2021,16(19):2973-2977
The change in the valence state of nanocluster can induce remarkable changes in the properties and structure. However, achieving the valence state changes in nanoclusters is still a challenge. In this work, we use Cu2+ as dopant to “oxidize” [Ag62S12(SBut)32]2+ (4 free electrons) to obtain the new nanocluster: [Ag62−xCuxS12(SBut)32]4+ with 2 free electrons. As revealed by its structure, the [Ag62−xCuxS12(SBut)32]4+ (x=10∼21) has a similar structure to that of [Ag62S12(SBut)32]2+ precursor and all the Cu atoms occupy the surface site of nanocluster. It′s worth noting that with the Cu atoms doping, the [Ag62−xCuxS12(SBut)32]4+ nanocluster is more stable than [Ag62S12(SBut)32]2+ at higher temperature and in electrochemical cycle. This result has laid a foundation for the subsequent application and exploration. Overall, this work reveals crystals structure of a new Ag−Cu nanocluster and offers a new insight into the electron reduction/oxidation of nanocluster. 相似文献
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The triply bonded heavier main-group compounds have a textbook trans-bent geometry, in contrast to a familiar linear form found for the lightest analogues. Strikingly, the unexpected linear group 13 E≡E triple bonds were herein found in the D4h-symmetry E2Li62+ clusters, and they possess a large barrier (>18.0 kcal/mol) towards the dissociation of Li+. The perfectly surrounded Li4 motifs and two linear coordinated Li atoms strongly suppress the increasing nonbonded electron density of heavier E atoms, making two degenerate π bonds and one multi-center σ bond in linear heavier main-group triple bonds. The surrounding Li6 motifs not only creates an effective electronic structure to form a linear E≡E triple bond, but the resulting electrostatic interactions account for the highly stable global E2Li62+ clusters. 相似文献
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在玻碳电极上制备了聚合酸性蓝62(PAB)膜电极,并用于双酚A(BPA)的电化学测定。BPA在PAB膜修饰电极上产生一个灵敏的氧化峰,与裸电极相比,其峰电位负移100mV。氧化峰电流与BPA浓度在2.0×10-7~4.0×10-6 mol.L-1和8.0×10-6~2.0×10-4 mol.L-1范围内呈良好线性关系,检出限为2.0×10-8 mol.L-1。该法可用于实际样品中BPA的测定。 相似文献
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《Journal of Coordination Chemistry》2012,65(3):363-371
The 2D Zn(II) coordination polymer with 2,3-dicarboxypyridine acid (2,3-H2PDC) and dimethylamine (DMA) [Zn(2,3-PDC)(DMA)] n (1) was synthesized under solvothermal conditions and characterized by FT-IR spectroscopy, TGA and luminescent analysis. X-ray crystallographic studies of 1 reveal that this metal-organic complex has an interesting (3,4)-connected 2D network with binary nodes. The Zn ions are four-connected nodes and the 2,3-PDC ligands are three-connected nodes. Luminescent study indicates 1 has an emissive maximum at 403?nm in the solid state at room temperature. 相似文献
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采用密度泛函理论(DFT)方法, 在TZP基组水平下计算C62及其吡啶衍生物几何与电子结构, 在全优化构型基础上, 采用TD-DFT方法对其低激发态进行计算, 预测其电子吸收光谱. 结果表明, 四种异构体的电子光谱中, 特征吸收来自C62内部的跃迁贡献, 也包括取代基到C62的电子转移. 取代基中N原子位置对490 nm左右吸收带的强度有影响, 两种顺式结构表现较为明显, 而两种反式结构衍生物光谱特征基本相同. 相似文献
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《化学学报》2004,(24)
AKASHI,Mitsuru 615………………………………………………AN ,De Lie 1166……………………………………………………AN ,Deng Kui 15 5 1…………………………………………………AN ,Jing Yi 1171……………………………………………………AN ,Yue 5 40………………………………………………………AN ,Zhong Wei 2 0 73………………………………………………BAI,Hong Tao 461…………………………………………………BAI,Hua Ping 12 5 2…………………………………………………BAI,Yong Ping 3 77……………………………… 相似文献
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According to the 31P NMR spectroscopy, heteropolyacid (HPA) H6P2Mo18O62·nH2O (P2Mo18), -isomer of the Dawson structure, transforms upon heating above 80 °C partially (up to 30%) to -isomer, in which both polar groups Mo3O13 of the heteropolyanion are turned by 60° around the N3 axis, and partially to -isomer in which only one group is turned. The - and -isomers of P2Mo18 have been found for the first time. Their transformation into the -isomer occurs upon rehydration in one week in air and in 1 h in an aqueous solution. HPA P2Mo18 decomposes on heating up to 350 °C to HPA H3PMo12O40 (PMo12) and a previously unknown phase of the HPMo6I21 composition, which in its turn decomposes at 375 °C to molybdenyl phosphates and IiI3. The PMo12 decomposition occurs via two routes to form the same products at temperatures of 400 and 450 °C with corresponding exotherms of IiI3 crystallization. 相似文献
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本文采用"一锅法"合成了两种Mannich碱1-(3-氧代丁基)硫脲(OBT)和1-(3-氧代-3-苯丙基)硫脲(OPPT),并采用失重法和电化学研究方法研究了两种Mannich碱对H62黄铜在5%(w)NaHCO3水溶液中的缓蚀性能和吸附行为。结果表明:在5%NaHCO3水溶液中这两种化合物对H62黄铜均有较好的缓蚀效果,缓蚀效率大小顺序为OPPTOBT。并且OBT与OPPT均为阴极型缓蚀剂。两种化合物在铜表面上的吸附过程为放热过程,其在铜表面上的吸附行为服从Langmiur吸附等温式,属于物理吸附。 相似文献
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固相萃取-高效液相色谱-串联质谱法测定坚果中62种农药残留 总被引:1,自引:0,他引:1
《分析科学学报》2015,(6)
建立了固相萃取-高效液相色谱-串联质谱(SPE-HPLC-MS/MS)法测定坚果中62种农药残留的分析方法。样品以乙腈提取,经正己烷脱脂后,采用TPH固相萃取小柱净化。待测物经Zorbax Eclipse Plus C18柱(100×3.0mm,1.8μm)分离,以乙腈-0.1%甲酸为流动相,梯度洗脱;采用电喷雾正离子源、多重反应监测模式检测;以保留时间和特征离子对(母离子和两个碎片离子)信息比较进行定性和定量分析。62种农药在各自线性范围内相关系数均大于0.993;在核桃、杏仁、花生仁三种基质中方法的定量限(以S/N≥10计)为0.1~10.0μg/kg,1、2、4倍定量限3个加标水平下,回收率为71.2%~112.7%,相对标准偏差为5.8%~14.1%。该方法灵敏度高、重复性好,检出限能够满足国内外对农药残留的最高限量要求,适合于坚果中农药残留的测定。 相似文献
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合成了一系列Dawson型磷钼钒钴杂多酸盐Co<,n> H<,9-2n>P<,2>Mo<,15>V<,3>O<,62>(n=1-4),用傅立叶变换红外光谱表征了磷钼钒钴的结构.以乙苯为原料、H<,2>O<,2>为氧化剂、磷钼钒钴杂多酸盐为催化剂催化氧化乙苯制备苯乙酮.考察了催化剂种类及用量、助剂用量、H<,2>O<,2... 相似文献