季铵型阳离子蔗渣纤维素对甘蔗清汁的澄清研究

利用新型的季铵型阳离子蔗渣纤维素作为澄清剂,对甘蔗清汁进行吸附脱色研究.本实验在单因素试验结果的基础上,分别选取纯度提高率和色值降低率作为考查指标,利用SPSS软件进行正交试验的设计和数据分析.通过最佳工艺参数的优化试验,得出如下结论:反应温度为80℃、蔗汁中阳离子蔗渣纤维素复合物的加入量为0.4g/100mL甘蔗清汁、接触时间为40min、pH值8.     

Untersuchung von Wasser

Ohne Zusammenfassung     

Hydrogen Bonding in the Water Stabilized Structure of the Modified Unsymmetrically Substituted Viologen Chromophore, <Emphasis Type="Italic">N</Emphasis>-ethyl-<Emphasis Type="Italic">N</Emphasis>′-(2-phosphonoethyl)-4,4′-bipyridylium Dichloride

Abstract  

The crystal structure of the modified unsymmetrically N,N′-substituted viologen chromophore, N-ethyl-N′-(2-phosphonoethyl)-4,4′-bipyridinium dichloride 0.75 hydrate (1) has been determined. Crystals are triclinic, space group P−1 with Z = 2 in a cell with a = 7.2550(1), b = 13.2038(5), c = 18.5752(7) Å, α = 86.495(3), β = 83.527(2), γ = 88.921(2)°. The two independent but pseudo-symmetrically related cations in the asymmetric unit form one-dimensional hydrogen-bonded chains through short homomeric phosphonic acid O–H···O links [2.455(4), 2.464(4) Å] while two of the chloride anions are similarly strongly linked to phosphonic acid groups [O–H···Cl, 2.889(4), 2.896(4) Å]. The other two chloride anions together with the two water molecules of solvation (one with partial occupancy) form unusual cyclic hydrogen-bonded bis(Cl···water) dianion units which lie between the layers of bipyridylium rings of the cation chain structures with which they are weakly associated.     

Study of Sm-doped ZnO samples sintered in a nitrogen atmosphere and deposited on n-Si(1 0 0) by evaporation technique

The samarium doping zinc oxide (Zn_1-xSm_xO) with (x=0.0, 0.04, 0.05 and 0.17) polycrystalline thin films have been deposited on n-Si(1 0 0) substrate using thermal evaporation technique. Ceramic targets for deposition were prepared by the standard solid-state reaction method and sintered in nitrogen atmospheres. X-ray diffraction and scanning electron microscopy analyses show that the bulk and films features reveal wurtzite crystal structure with a preferential (1 0 1) crystallographic orientation and grows as hexagonal shape grains. According to the results of the Hall effect measurements, all the films show p-type conductivity, possibly a result of nitrogen incorporation into the Sm-doped ZnO samples. Magnetic measurements show that ferromagnetic behavior depends on the Sm³⁺ concentration. For a film with lower Sm₂O₃ contents (x=0.04), a phenomenon of paramagnetism has been observed. While, with further increase of Sm³⁺ contents (x=0.05) the ferromagnetic behavior has been observed at room temperature. However, at higher doping content of Sm³⁺, the ferromagnetic behavior was suppressed. The decrease of ferromagnetism with increasing doping concentration demonstrates that ferromagnetism observed at room temperature is an intrinsic property of Zn_1-xSm_xO films.     

Index computations in Rabinowitz Floer homology

In this note we study two index questions. In the first we establish the relationship between the Morse indices of the free time action functional and the fixed time action functional. The second is related to Rabinowitz Floer homology. Our index computations are based on a correction term which is defined as follows: around a nondegenerate Hamiltonian orbit lying in a fixed energy level a well-known theorem says that one can find a whole cylinder of orbits parametrized by the energy. The correction term is determined by whether the periods of the orbits are increasing or decreasing as one moves up the orbit cylinder. We also provide an example to show that, even above the Ma?é critical value, the periods may be increasing thus producing a jump in the Morse index of the free time action functional in relation to the Morse index of the fixed time action functional.     

Yrast states in81Br and82Br

Projectile and targetK-vacancy production probabilities in 4.6-, 5.8- and 7.3-MeV/a.m.u. U+U and U+Pb collisions are reported for impact parameters between 10 and 85 fm. These probability measurements are compared with available theory.     

光电直读光谱法测定稀土铝合金中La,Ce,Pr,Nd,Sm ,Si,Fe,Cu

本文报道了稀土铝合金中La,Ce,Pr,Nd,Sm,Si,Fe,Cu的光电直读光谱测定，对光源的激发方式及最佳工作条件进行了选择，应用KH－5高能预火花光源，采用单向全功率放电，先冲洗3秒，然后预燃5秒，曝光10秒。各元素谱线间无干扰，。使用固体试样，样品处理简单。经试验验证该法简便快速，精密度准确度高，含量在0．001％－0．002％之间RSD＜6％，0．02％－0．3％之间RSD＜3％，标准样品的测定值与准确值吻合较好，结果令人满意。