CFD analysis of pneumatic conveying in a double-tube-socket (DTS (R)) pipe

A pipeline with a bypass is widely used for the pneumatic conveying of material. The double-tube-socket (DTS (R)) technology, which uses a special inner bypass, represents the current state of the art. Here, a new methodology is proposed based on the use of computational fluid dynamics (CFD) to predict the energy consumption of DTS conveying. The predicted results are in good agreement with those from pilot-scale experiments. (C) 2010 Elsevier Inc. All rights reserved.

NEW METHODOLOGY FOR THE ESTIMATION OF ENERGY CONSUMPTION IN A DOUBLE-TUBE-SOCKET (DTS (R)) PNEUMATIC CONVEYING

A new methodology based on the use of CFD is proposed to estimate the energy consumptions in a DTS (DOUBLE-TUBE-SOCKET) pneumatic conveying. A simple computational program based on this methodology is developed. It can directly give the lowest energy consumption and the compatible gas consumption by only input the distance of conveying and the conveying tonnage. This computational program has been validated through our experimental work.

R IBLL终端LA SCAR阵列探测器PM T高压控制系统的研制

介绍了R IBLL终端LA SCAR上PM T阵列电源高压控制系统。该系统以当今工程控制中常用的微型计算机作为核心器件,采用合适的外围电路达到了对PM T阵列稳定、可靠的控制,在现场测试中取得了良好的效果。

高离化态S~(q+)与H_2碰撞中H_2~(r+)的库仑爆炸及解离过程研究

采用位置灵敏探测器和散射离子 反冲离子飞行时间技术测量了 90 0keV的Sq + +H2 碰撞产生的H+ 碎片的能量分布 ,实验表明部分Hr+ 2 发生解离。基于蒙特卡罗方法 ,建立了程序模拟离子与分子碰撞中的反冲离子飞行时间谱。模拟结果与实验 (S2 + +H2 ,S2 + +He)测量到的TOF谱进行了分析比较 ,并进行了定性讨论。

General SU(2)(L) x SU(2)(R) x U(1)(EM) sigma model with external sources, dynamical breaking and spontaneous vacuum symmetry breaking

We give a general SU(2)(L) x SU(2)(R) x U(1)(EM) sigma model with external sources, dynamical breaking and spontaneous vacuum symmetry breaking, and present the general formulation of the model. It is found that sigma and pi(0) without electric charges have electromagnetic interaction effects coming front the internal structures. A general Lorentz transformation relative to external sources J(gauge) - (J(A mu) J(A mu)(kappa)) derived, using the general Lorentz transformation and the four-dimensional current of nuclear matter of the ground si ate with J(gauge) = 0, we give the four-dimensional general relations between the different currents of nuclear matter systems with J(gauge) not equal 0 and those with J(gauge) = 0. The relation of the density's coupling with external magnetic field is derived, which conforms well to dense nuclear matter in a strong magnetic field. We show different condensed effects in strong interaction about fermions and antifermions, and give the concrete scalar and pseudoscalar condensed expressions of sigma(0) and pi(0) bosons. About different dynamical breaking and spontaneous vacuum symmetry breaking, the concrete expressions of different mass spectra are obtained in field theory. This paper acquires the running spontaneous vacuum breaking value sigma'(0), and obtains the spontaneous vacuum breaking in tenus of the running sigma'(0), which make nucleon, sigma, and pi particles gain effective masses. We achieve both the effect of external sources and nonvanishing value of the condensed scalar and pseudoscalar paticles. It is deduced that the masses of nucleons, sigma and pi generally depend on different external sources.

Ginsenoside R-e increases fertile and asthenozoospermic infertile human sperm motility by induction of nitric oxide synthase

We investigated the effects of Ginsenoside R-e on human sperm motility in fertile and asthenozoospermic infertile individuals in vitro and the mechanism by which the Ginsenosides play their roles. The semen samples were obtained from 10 fertile volunteers and 10 asthenozoospermic infertile patients. Spermatozoa were separated by Percoll and incubated with 0, 1, 10 or 100 mu M of Ginsenoside R-e. Total sperm motility and progressive motility were measured by computer-aided sperm analyzer (CASA). Nitric oxide synthase (NOS) activity was determined by the H-3-arginine to H-3-citrulline conversion assay, and the NOS protein was examined by the Western blot analysis. The production of sperm nitric oxide (NO) was detected using the Griess reaction. The results showed that Ginsenoside R-e significantly enhanced both fertile and infertile sperm motility, NOS activity and NO production in a concentration-dependent manner. Sodium nitroprusside (SNP, 100 nM), a NO donor, mimicked the effects of Ginsenoside R-e. And pretreatment with a NOS inhibitor N-omega-Nitro-L-arginine methyl ester (L-NAME, 100 mu M) or a NO scavenger N-Acetyl-L-cysteine (LNAC, 1 mM) completely blocked the effects of Ginsenoside R-e. Data suggested that Ginsenoside R-e is beneficial to sperm motility, and that induction of NOS to increase NO production may be involved in this benefit.

以转座子Tn5作弗氏中华根瘤菌的可识别生态学标记的研究──Tn5的水平转移及其对R．frediiTn5突变株运动的影响

将一株弗氏中华根瘤菌（Ｒ．ｆｒｅｄｉｉ）ＱＢ１１３０的Ｔｎ５插入突变株ＯＮ－２用于生态学研究，以评估Ｔｎ５在自然环境中的水平转移以及各种水势下Ｔｎ５对突变株ＯＮ－２在土壤中运动的影响．试验表明，在自然潮湿的土壤中，Ｔｎ５本身的水平转移频率很低，且与Ｔｎ５插入相关的突变株卡那霉素抗性表型标记在非选择性平板上连续传４０代后仍然稳定．突变株ＯＮ－２与相对应的野生型菌株ＱＢ１１３０在各种相同水势的土壤中的运动无明显差异（Ｐ＝０．０１），表明Ｔｎ５的插入不影响突变株的运动．因此，Ｔｎ５可作为研究Ｒ．ｆｒｅｄｉｉ基因工程菌大回应用的一个稳定有效的生态学标记．

Investigation of Chemical Bond Characteristics, Thermal Expansion Coefficients and Bulk Moduli of alpha-R2MoO6 and R2Mo2O7 (R = rare earths) by Using a Dielectric Chemical Bond Method

Theoretical researches are performed on the alpha-R2MoO6 (R = Y, Gd, Tb Dy, Ho, Er, Tm and Yb) and pyrochlore-type R2Mo2O7 (R = Y, Nd, Sm, Gd, Tb and Dy) rare earth molybdates by using chemical bond theory of dielectric description. The chemical bonding characteristics and their relationship with thermal expansion property and compressibility are explored. The calculated values of linear thermal expansion coefficient (LTEC) and bulk modulus agree well with the available experimental values. The calculations reveal that the LTECs and the bulk moduli do have linear relationship with the ionic radii of the lanthanides: the LTEC decreases from 6.80 to 6.62 10(-6)/K and the bulk modulus increases from 141 to 154 GPa when R goes in the order Gd, Tb Dy, Ho, Er, Tm, and Yb in the alpha-R2MoO6 series; while in the R2Mo2O7 series, the LTEC ranges from 6.80 to 6.61 10(-6)/K and the bulk modulus ranges from 147 to 163 GPa when R varies in the order Nd, Sm, Gd, Tb and Dy.

Bonding Characteristics, Thermal Expansibility, and Compressibility of RXO4 (R = Rare Earths, X = P, As) within Monazite and Zircon Structures

Systematically theoretical research was performed on the monazite- and zircon-structure RXO4 (R = Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; X = P, As) series by using the chemical bond theory of dielectric description. The chemical bond properties of R-O and X-O bonds were presented. In the zircon phase, the covalency fractions of X-O bonds increased in the order of V-O < As-O < P-O, which was in accordance with the ionic radii and electronegative trends, and the covalency fractions of R-O bonds varied slightly due to the lanthanide contraction. While in the monazite phase, both R-O and X-O bonds were divided into two groups by their covalency fractions.

Chemical bond characteristics, thermal expansion property and compressibility of AR(2)O(4) (A = Ca, Sr, Ba; R = rare earths)

Theoretical researches were performed on the CaFe2O4-type binary rare earth oxides AR(2)O(4) (A = Ca, Sr, Ba; R = rare earths) by using chemical bond theory of dielectric description. The chemical bond properties of these crystals were explored, and then the thermal expansion property and compressibility were studied. The theoretical values of linear thermal expansion coefficient (LTEC) and bulk modulus were presented. The calculations revealed that the LTECs and the bulk moduli do have linear relationship with the ionic radii of the rare earths. In the cases of Sc and Y, both the LTEC and bulk modulus values are larger than the lanthanide series. We attribute this to the difference in the electronic configuration between Sc (Y) and lanthanide series. For SrY2O4 and BaY2O4 crystals, the theoretical values of LTEC and bulk modulus agree well with experimental ones.

Implantation of Nafion (R) ionomer into polyvinyl alcohol/chitosan composites to form novel proton-conducting membranes for direct methanol fuel cells

A series of cost-effective, proton-conducting composite membranes, comprising of Nafion (R) ionomer, chitosan (CS). and polyvinyl alcohol (PVA), is successfully prepared. By taking advantage of the strong electrostatic interactions between Nafion (R) ionomer and CS component, Nafion ionomer is effectively implanted into the PVA/CS composite membranes, and improves proton conductivity of the PVA/CS composite membranes. Furthermore, this effect dramatically depends on the composition ratio of PVA/CS, and the optimum conductivity is obtained at the PVA/CS ratio of 1:1. The developed composite membranes exhibit much lower methanol permeability compared with the widely used Nafion (R) membrane, indicating that these novel membranes have great potential for direct methanol fuel cells (DMFCs).