碱—氧—蒽醌蒸煮法制取麦草浆纤维素的酶解

用碱－氧－蒽醌蒸煮麦草所得纤维素为原料，研究了纤维素酶解的影响因素。结果表明：预处理后的麦草纤维素，其木质素含量较低，而酶解率和木质部除率均较高，在４５～５０℃、ｐＨ为４．４、底物与酶量之比为１：０．２、反应时间为３０ｈ、转速为１００ｒ／ｍｉｎ时，可获得较理想的酶解率和木质素脱除率，二者分别可达７４．５％和１９．２％。     

麦草碱—氧蒸煮脱木素

用碱－氧蒸者麦草脱木素，考察了工艺条件对麦草脱木素的影响。结果表明：适宜的麦草脱木素的条件为温度１６０℃，碱浓度８％，氧压０．８ＭＰａ，固液比０．８，保温时间１ｈ．同时，通过ＩＲ和＾１Ｈ－ＮＭＲ对木素结构进行了分析。     

Fe—Ga—C熔体的热力学研究

以碳管炉为加热体。在氩气保护下研究了铁液中镓含量对碳的饱和熔解度的影响。在镓含量为０．１１％～９．３３％的浓度范围内，通过实验得出了不同温度下铁液中镓含量与碳的饱和溶解度的关系。并根据Ｓｃｈｅｎｃｋ的相互作用参数式，得出铁液中碳与镓的相互作用系数与温度的关系式。     

氢—氧火焰切割的节能效果和经济意义

利用氢－氧发生器产生氢气进行火焰切割其成本仅为乙炔气的１５％。氢－氧发生器可用于手工切割和半自动切割，安全可靠，使用方便，经济效益显著。     

RE／S值对控轧低碳Mn—Nb—RE钢硫化物成分和形貌的影响

用扫描电测定了含０．０４１％－０．０７６％ＲＥ的低碳Ｍｎ－Ｎｂ－ＲＥ钢中硫化物的成分，大小和形貌。ＲＥ／Ｓ值为２．８－３．０时，钢中的硫化物充分变质。     

碳还原锆英石的Si—C—O系中C和CO优势图

对碳还原锆英石中ＳｉＯ２进行了温度、配碳量，时间和工的实验研究，得到相应的脱硅率的影响规律，建立了Ｓｉ－Ｃ－Ｏ系中Ｃ－ＣＯ型优势图，讨论了ＳｉＯ分和ＳｉＯ２活度等对脱硅率的影响，得到温度与ＳｉＯ２最低含量的理论关系，配碳量为７．５％时的脱硅率达到极大值９７．２２％，在１８７３－２２７３Ｋ温度范围内的化学反应表观活化能为２８２．０ＫＪ／ｍｏｌ，反应的主要限制环节是锆英石的热分解。     

CeCl_3—SrCl_2—NaCl三元体系相图的研究

利用ＤＴＡ研究了ＣｅＣｌ＿３－ＳｒＣｌ＿２－ＮａＣｌ三元体系相图。结果表明：本体系属简单低共熔体系。相图内有对应于ＣｅＣｌ＿３、ＳｒＣｌ＿２和ＮａＣｌ三个液相面，三条二次结晶线和一个三元低共熔点以３４．７ｗｔ－％ＣｅＣｌ＿３，４３．６ｗｔ－％ＳｒＣｌ＿２，２１．７ｗｔ％ＮａＣｌ，４８８℃）。     

8—羟基喹啉重量法测定氧化钼中的Mo

本方法以８－羟基喹啉钼重量法测定原材料氧化钼中的Ｍｏ．氧化钼粉末用过氧化钠在白金坩埚中熔融，用沸水浸出，不经分离直接用ＥＤＴＡ掩蔽其它金属离子的干扰，调节ｐＨ值至为５，加热近沸，立即滴加８－羟基喹啉溶液，沉淀用砂芯玻璃坩埚过滤，干燥，称重。本法的回收率为９８．８７％－１００．３５％，相对标准偏差为０．１６％（ｎ＝１１）。     

应用氧—燃技术提高电炉产量

由于电，煤差价的缘故，一些电炉炼钢厂采用氧－燃喷枪提供部份电炉生产所需的热能。事实上，在大多数情况下，应用氧－燃技术既可节约能源又可改进工艺。氧－燃喷枪还可应用于钢包和炉体预热。     

石墨炉原子吸收光谱法连续测定化探样品中金,银,镓的研究

本文提出在盐酸－碘化钾介质中，用ＭＩＢＫ萃取，硫脲反萃取，石墨炉原子吸收光谱法连续测定化探样品中的Ａｕ、Ａｇ、Ｇａ三种元素，经萃取反萃取既分离了干扰元素，又能提高测定灵敏度和精密度．文中研究了不同石墨管对测定的影响，用Ｌ＇ＶＯＶ理论探讨镍对镓的基体改进作用和机理．金、银、镓测定的相对标准偏差分别为５．２％、４．８％、６．２％，回收率在９３．３％～１０６．５％之间．     

Gallium-67 radiotoxicity in human U937 lymphoma cells

Promising clinical results have been obtained with radiolabeled antibodies in lymphoma patients. The higher uptake by lymphomas of 67Gallium (67Ga) compared with monoclonal antibodies makes selective radiotherapy by the widely available 67Ga appealing. However, the gamma radiation of 67Ga used in scintigraphy is considered to be almost non-toxic to lymphoma cells. However, in addition to photon radiation 67Ga emits low energy Auger electrons and 80-90 keV conversion electrons which could be cytotoxic. The objective of the present study was the assessment of radiotoxicity of 67Ga on a lymphoid cell line: U937. Proliferation (MTT-assay) and clonogenic capacity (CFU-assay) were measured after 3 and 6 days incubation with 10, 20 and 40 microCi ml-1 67Ga. Growth inhibition was 36% after 3 days incubation and 63% after 6 days incubation with 40 microCi 67Ga ml-1. Clonogenic capacity was reduced by 51% after 3 days and 72% after 6 days incubation with 40 microCi ml-1 67Ga. A survival curve showed an initial shoulder and became steeper beyond 200-250 pCi cell-1 (low linear energy transfer type). Iso-effect doses of 67Ga and 90Yttrium (90Y) were determined. The iso-effect dose of 40 microCi 67Ga ml-1 (cumulative dose of conversion electrons 306 cGy) was 2.5 microCi 90Y ml-1 (cumulative dose 494 cGy) and the iso-effect dose of 80 microCi 67Ga ml-1 was 5.0 microCi 90Y/ml. The main cytotoxic effect of 67Ga seems to be induced by the 80 keV conversion electrons. We conclude that the conversion electrons of 67Ga have a cytotoxic effect on U937 cells and that in our experiments a 16-fold higher microCi-dose of 67Ga than of 90Y was needed for the same cytotoxic effect. We believe that 67Ga holds promise for therapeutic use.     

铟镓锗镉在铜锌铅混合精矿氧压酸浸工艺中的分布及回收方法探讨

介绍了在作者研究的铜锌铅混合精矿氧压酸浸工艺中，混合精矿中含有的铟镓锗镉等稀有金属元素在工艺中的分布走向情况。结果表明：在氧压酸浸工艺中．铟镓锗镉等稀有元素都被浸出，并在浸出液提取铜锌工艺产生的中间产物中得到不同程度的富集。本文还对混合精矿中铟镓锗镉的回收途径进行了探讨。     

Gallium citrate Ga 67 scanning: clinical usefulness in lymphoma patients

Gallium citrate Ga 67 (67Ga) scans were performed in 50 consecutive lymphoma patients who underwent routine staging. The overall accuracy of 67Ga scans was greater than 80% for all nodal sites except the spleen (68%). Sensitivity was greater than 88% in the neck and mediastinum, 67% in the abdomen-pelvis, and 33% for the spleen. Specificity was greater than 85% for all nodal sites except for the mediastinum (67%). The accuracy of pedal lymphangiograms was 75%, sensitivity 87%, and specificity 68%. Gallium 67 scans complemented the lymphogram in the abdomen-pelvis but, due to limited sensitivity and high number of equivocal studies (16%), did not replace it. Infraclavicular, pectoral, and mediastinal lesions were detected by 67Ga scans when missed by other means. In 20% to 25% of patients, 67Ga scans provided information not afforded by other diagnostic studies and are therefore considered an important staging procedure for lymphoma patients.     

Effects of oxygen pressure on La_3Ga_5SiO_(14) thin films grown by pulsed laser deposition

La3Ga5SiO14 thin films were grown on Si(100) substrates by pulsed laser deposition at several oxygen pressures(5,10,and 20 Pa).The effects of oxygen pressure on the structural and morphological characteristics of the films were investigated using X-ray diffraction,atomic force microscopy,and scanning electron microscopy.X-ray diffraction results showed the intensity of lines from crystallites oriented along the(300) and(220) planes increased as the oxygen pressure was increased to 20 Pa.The deposited films ...     

Cell cycle dependency of 67gallium uptake and cytotoxicity in human cell lines of hematological malignancies

67Gallium (67Ga) is a radionuclide which accumulates in hematological malignancies and is used for diagnostic imaging. We investigated in this in vitro study the cell cycle dependency of cellular uptake and cytotoxicity of 67Ga. Cell cycle synchronization of cells was achieved by counterflow centrifugal elutriation and the use of cytostatic drugs. The human lymphoma cell lines U-937 and U-715 were used and in elutriation experiments we also used the leukemic cell line HL-60. The transferrin receptor (CD71) expression, 67Ga uptake and cell proliferation inhibition were the parameters measured. We also studied cytotoxicity in various schedules for combination of 67Ga and drugs and the residual proliferative capacity was measured. The CD71 expression in the three cell lines increased from 106-177% on S phase cells and from 118-233% on G2M cells, as compared to the G0/G1 cell fraction. The 67Ga uptake varied from 108-127% for S cells and 128-139% for G2M cells. The drugs chosen induced cell cycle phase accumulation in S and/or G2M phase during preincubation. 67Ga preincubation induced accumulation in the G2M phase. Almost all combinations of 67Ga and drugs resulted in a non-interactive effect, except for methotrexate which resulted in an antagonistic effect. No preferential effect of any of the incubation schemes was seen. CD71 expression and 67Ga uptake were increased in S and G2M cells. Combination of 67Ga with drugs which arrest cells in these cell cycle phases did not result in a change in cytotoxicity. However, these results implicate that 67Ga and the cytostatic drugs tested except for methotrexate might be used together or sequentially in therapy.     

Oxidation of an Fe-Cr-Al-Y-Zr alloy forming an alumina scale in a Ga<Subscript>2</Subscript>O atmosphere at 1473 K

The oxidation of an Fe-Cr-Al-Y-Zr alloy exposed to a Ga atmosphere at 1473 K has been investigated by an encapsulation method. A Ga/Ga₂O₃ mixture was placed within the quartz ampoules to establish the Ga₂O and the O₂ partial pressures enveloping a Fe-Cr-Al-Y-Zr alloy (specifically, 72.8Fe-22Cr-5Al-0.1Y-0.1Zr by mass pct), which contains minor additions of yttrium and zirconium to improve scale adherence. A deoxidized Ar atmosphere surrounded the ampoules to control oxygen permeation through the silica wall. The Fe-Cr-Al-Y-Zr alloy developed an Al₂O₃ scale growing parabolically and protecting the substrate from gallium attack for 5, 10, 20, 40, and 50 days, as examined with a scanning electron microscope (SEM) and energy dispersive X-ray (EDX) analysis. The Ga₂O atmosphere decomposes to liquid Ga and Ga₂O₃ on the alloy surface, but gallium species do not penetrate the oxide layer according to the limits of detection for EDX analysis. Defect equilibria incorporating Ga₂O are presented with neutral interstitial oxygen to explain the oxidation of the Fe-Cr-Al-Y-Zr alloy.     

Conjugation of the monoclonal antibody 17-1A with the nitroacridine compound C921 with the poly-L-lysine as an intermediate agent

Transferrin and transferrin receptors play an important role in the transport of iron into the brain. To determine whether gallium enters the brain by the same mechanism, uptakes of 67Ga and 59Fe have been compared under controlled conditions. Rates of gallium penetration into brain (K(in)) were four times slower than those for 59Fe. K(in) for 67Ga when infused with citrate were 0.88 +/- 0.24 and 0.94 +/- 0.39 x 10(-3) ml g-1h-1 for cerebral hemisphere and cerebellum, respectively. When infused as the transferrin complex, 67Ga uptake into the brain was not different from that when infused with citrate. The presence of the anti-transferrin receptor antibody OX-26 significantly reduced uptake of 59Fe by 60% and 64% into cerebral hemisphere and cerebellum, respectively. By contrast, pretreatment of rats with OX-26 enhanced the uptake of 67Ga into brain, particularly when infused with citrate; mean increases in uptake of 67Ga were 120% and 144% for cerebral hemisphere and cerebellum, respectively. Purified 67Ga-transferrin was also taken up into both brain regions examined in the presence of OX-26. These results indicate that the transport of non-transferrin bound gallium is an important mechanism for gallium uptake into brain.     

Ni-Mn-Ga磁控形状记忆合金中的马氏体相变

文章采用电弧熔炼法熔炼Ni48Mn31Ga21和Ni2MnGa两种合金,并对这两种合金进行了热处理,借助交流磁化率测定、金相显微镜观察、X射线以及磁化曲线等手段研究了Ni-Mn-Ga磁控形状记忆合金中的马氏体相变。结果表明：（1）Ni48Mn3lGa21合金在室温下发生了马氏体转变,而Ni2MnGa合金在室温下则未发生马氏体转变;（2）室温下Ni2MnGa合金的饱和磁化强度比Ni48Mn3lGa21合金高;对于Ni48Mn31Ga2l合金,其马氏体态的饱和磁化强度要高于奥氏体态。     

Electroextraction of neodymium from LiCl-KCl melt using binary liquid Ga-Al cathode

The electrochemical behaviour of Nd(Ⅲ) ion was investigated on inert W,active Ga and Ga-AI cathodes.It is established that the reduction of Nd(Ⅲ) ion on the inert electrode is a consecutive two-step process while that on the active electrodes is a one-step process.The apparent standard potential of the Nd(Ⅲ)/Nd redox couple at different temperatures was determined by open-circuit chronopotentiometry and semi-differential method,and the relationship between temperature and apparent standard poten...