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991.
Counterion effects of nickel and sodium dodecylbenzene sulfonate adsorption to multiwalled carbon nanotubes in aqueous solution 总被引:3,自引:0,他引:3
Batch experiments were conducted to elucidate the adsorption of a widely used anionic surfactant (sodium dodecylbenzene sulfonate (SDBS)) and nickel on multiwalled carbon nanotubes (MWCNTs). Counterion effect on the removal of SDBS and nickel by using MWCNTs was also studied. The microscopic changes of MWCNTs before and after nickel and SDBS adsorption were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). X-ray photoelectron spectroscopy (XPS) was performed to study the adsorption mechanism of nickel at a molecular level. The spectroscopic analysis indicated that the adsorption mechanism was mainly attributed to chemical interaction between nickel and the surface functional groups of MWCNTs and surface adsorbed SDBS. The adsorbed SDBS on MWCNTs could lead to the modification of the MWCNT surfaces and partial complexation of nickel with SDBS adsorbed on MWCNTs. MWCNTs are efficient material in the removal of SDBS and nickel from large volume of wastewater. 相似文献
992.
A novel soil stabilizer based on poly-amino acid - polyaspartic acid (PASP) and its copolymer which modified by xanthan gum
(XG) was studied to increase soil particle compressive strength and resistance to wind erosion. Due to its unique property,
the stabilizer aggregated individual soil particles and formed crust. The sample compressive strength increased from 0.175
to 0.612 MPa and the wind erosion modulus reduced from 22.43 to 10.56 g·m−2·min−1 after the 1% PASP hydrogel was applied by 1.67 Lm−2 (1 cm of crust). The soil water content was higher than the control due to the polymer’s excellent water-retaining property.
The polymer had no negative influence on seed germination and growth. The biodegradability experiment showed that PASP was
easy to biodegrade and therefore it was safe to apply in the field.
This work was presented at 13
th
YABEC symposium held at Seoul, Korea, October 20–22, 2007. 相似文献
993.
简介了注塑模内贴标成型原理、工艺和应用发展趋势,根据实际产品的应用案例分析了注塑模内贴标在塑料产品成型过程中的影响因素和工艺要点,提出了模内贴标塑料模具的特点及其设计的一般原则,分析了模内贴标产品的常见缺陷,并给出了改善措施. 相似文献
994.
Ye M Hu J Peng M Liu J Liu J Liu H Zhao X Tan W 《International journal of molecular sciences》2012,13(3):3341-3353
Aptamers are single-stranded oligonucleotides of DNA or RNA that bind to target molecules with high affinity and specificity. Typically, aptamers are generated by an iterative selection process, called systematic evolution of ligands by exponential enrichment (SELEX). Recent advancements in SELEX technology have extended aptamer selection from comparatively simple mixtures of purified proteins to whole living cells, and now cell-based SELEX (or cell-SELEX) can isolate aptamers that bind to specific target cells. Combined with nanotechnology, microchips, microfluidic devices, RNAi and other advanced technologies, cell-SELEX represents an integrated platform providing ultrasensitive and highly specific tools for clinical medicine. In this review, we describe the recent progress made in the application of cell-SELEX for diagnosis, therapy and biomarker discovery. 相似文献
995.
Xing-wu Tan Bai-mu Wang Ye Wang Shu-zhong Zhan 《Inorganic chemistry communications》2010,13(9):1061-1063
The Mannich reaction of 2-aminoethanol, 2-tert-butyl-4-methylphenol, and formaldehyde at the ratio sets of 1:2:2 provided a new ligand, N-(1-ethanol)-N,N-bis(3-tert-butyl-5-methyl-2-hydroxybenxyl)amine (H3L). In the presence of base, H3L reacted with FeCl3·6H2O to form a dinuclear Fe(III) complex [Fe2L2] 1. The value of μeff at room temperature (5.95 μB), is much less than the expected spin-only value (8.37 μB) of two high spin (hs) Fe3+ (S = 5/2) ions [μ = g[∑ ZS(S + 1)]1/2], indicating there were strong interactions between Fe3+ ions. The effective magnetic moment (μeff) decreased abruptly with cooling to a minimum value of 0.1 μB at 2 K. It was worth noting that Fe3+ ions of 1 exhibited thermally induced quartet ? doublet spin transitions, and these transitions were abrupt. The magnetic behaviors of 1 denoted the occurrence of intramolecular anti-ferromagnetic interactions. J (? 13.58 cm? 1) agrees with the result from Gorun–Lippard equation, ? J (cm? 1) = Aexp(BP(Å) = 12.9). 相似文献
996.
Dietary Inclusion of Tea Catechins Changes Fatty Acid Composition of Muscle in Goats 总被引:1,自引:0,他引:1
This study was conducted to examine dietary tea catechins (TC) supplementation on the fatty acid composition of muscle and
ruminal bacteria in goats fed a maize stover-based diet. Forty goats, 8 months old (16.2 ± 1.2 kg), were randomly divided
into four equal groups (10 animals in each group) and assigned to four experiment diets with TC supplementation at four levels
(0, 2,000, 3,000 and 4,000 mg TC/kg feed, namely TC0, TC2000, TC3000 and TC4000, respectively). After a 60-day feeding period,
all the goats were slaughtered and sampled. The results showed that dietary TC inclusion increased the average daily gain
(ADG), protein content in the semimembranosus muscle and dry matter in the longissimus dorsi muscle (LD). Dietary TC supplementation increased the ratio of n-6 to n-3 fatty acid, the ratio of polyunsaturated fatty
acids to saturated fatty acids was higher in TC3000 and TC4000 than in TC0 and TC2000 for LD. The current results implied
that dietary inclusion of a suitable TC dose could improve the growth performance and increase the proportions of unsaturated
fatty acids in muscle, and the biohydrogenation of ruminal microorganisms might change the profiles of fatty acids in the
muscle of growing goats. 相似文献
997.
Gang Wang Zhentao Wang Wei Wang Rujie He Kaixuan Gui Caiwang Tan Wei Cao 《Ceramics International》2019,45(8):10223-10229
In this paper, brazing behaviors between ZrB2SiC and Ti6Al4V by Cu foam interlayer were studied. The microstructure, formation mechanism, mechanical property and fracture surface of the joints were systematically studied. The results showed that the phases in the joints were α+β-Ti, TiCu, Ti2Cu, Cu(s, s), TiC, TiB2 and Ti3SiC2. An optimum shear strength reached up to 435??MPa?at a brazing temperature of 910?°C and holding time of 20?min. Such a shear strength was 90?MPa higher than the one without the Cu foam. The obtained high shear strength of joint was discussed from microstructure and residual stress. With the increase of brazing time, Cu(s,s) gradually disappeared and the content of Ti2Cu intermetallic compound increased, which was harmful for the joint. Furthermore, the residual stress of joint with Cu foam was calculated to be 324?MPa, lower than the one without Cu foam interlayer. 相似文献
998.
999.
铜铁试剂(CUP)—示波计时电位法直接测定天然水和饮用水中的铝含量。在0.5 mol/L(NH_4)_2SO_4-NH_3·H_2O(pH值=5.4)缓冲溶液中,加入铝后,铝—CUP配合物切口电位为-1.20V,切口深度在7.2×10~(-7)~3.2×10~(-5)mol/LAl范围内有线性关系,检测下限为5.8×10~(-7)mol/L。在2.0×10~(-5)mol/L时相对标准偏差为5.1(n=10)。应用该法测定了天然水和饮用水中铝含量,并同ICP/AES所获结果进行了对照。结果基本一致。 相似文献
1000.