Improving chill control in iron powder treated slightly hypereutectic grey cast irons

Recent studies revealed that in eutectic to slightly hypereutectic grey irons （CE = 4.3%-4.5%） the presence of austenite dendrites provides an opportunity to improve the cast iron properties, as a high number of eutectic cells are ＂reinforced＂ by austenite dendrites. An iron powder addition proved to be important by promoting dendritic austenite in hypereutectic irons, but was accompanied by adverse effect on the characteristics of potential nuclei for graphite. The purpose of the present paper is to investigate the solidification pattern of these irons. Chill wedges with different cooling moduli （CM = 0.11 - 0.43 cm） were poured in resin bonded sand and metal moulds. Relative clear / mottled / total chill measurement criteria were applied. Iron powder additions led to a higher chill tendency, while single inoculation showed the strongest graphiUzing effect. The various double treatments show an intermediate position, but the inoculant added after iron powder appears to be the most effective in reducing base iron chill tendency, for all cooling moduli and chill evaluation parameters. This performance reflects the improved properties of （Mn,X）S polygonal compounds as nucleation sites for graphite, especially in resin bonded sand mould castings. Both austenite and graphite nucleation benefit from a double addition of iron powder ＋ inoculant, with positive effect on the final structure and chill tendency.

Zhichan powder regulates nigrostriatal dopamine synthesis and metabolism in Parkinson's disease rats

In this study, rat models of Parkinson＇s disease induced by substantia nigra injection of 6-hydroxy-dopamine were intragastrically administered Zhichan powder daily for 50 days. Reverse transcription PCR results showed that tyrosine hydroxylase mRNA expression in the rat substantia nigra was significantly increased, while monoamine oxidase B mRNA expression was significantly decreased in the Zhichan powder group, compared with the model group. In addition, the levels of striatal dopamine and homovanillic acid, the ratio of dopamine to homovanillic acid, and the activity of blood superoxide dismutase were all higher in the Zhichan powder group than in the model group but the content of malondialdehyde in blood was lower. Our experimental findings indicate that Zhichan powder has an antioxidant effect, it can regulate the expression of monoamine oxidase B and tyrosine hydroxylase in the substantia nigra of Parkinson＇s disease rats, and it can facilitate the secretion of striatal dopamine and its metabolite homovanillic acid.

Effects of Zhichan powder on signal transduction and apoptosis-associated gene expression in the substantia nigra of Parkinson's disease rats

Previous studies have shown that Zhichan powder elevated immunity and suppressed oxidation in mice. Rat models of Parkinson＇s disease were induced by stereotaxically injecting 6-hydroxydopamine into the substantia nigra. The rat models were intragastrically treated with Zhichan powder, which is composed of milkvetch root, ginseng, bunge swallowwort root, himalayan teasel root. Magnolia officinalis, Ligustrum lucidum Ait. and szechwan Iovage rhizome. Immunohistochemistry and reverse transcription-PCR results demonstrated that mRNA and protein expression of tumor necrosis factor receptor 1, Fas, caspase-8, cvtochrome C, Bax, casDase-3, and p53 significantly increased, but Bcl-2 expression significantly decreased in the substantia nigra of rats with Parkinson＇s disease. Following Zhichan powder administration, mRNA and protein expression of tumor necrosis factor receptor 1, Fas, caspase-8, cytochrome C, Bax, caspase-3, and p53 diminished, but Bcl-2 expression increased in the rat substantia nigra. These results indicate that Zhichan powder regulates signal transduction protein expression, inhibits apoptosis, and exerts therapeutic effects on Parkinson＇s disease.

Characterization of functionally graded ZrO_2 thermal barrier coatings sprayed by supersonic plasma spray with dual powder feed ports

The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports system. The thermal shock experiment of FG-TBCs specimens was carried out by means of the automatic thermal cycle device, in which the samples were heated to 1200℃ by oxygen-acetylene flame jet then water-quenched to ambient temperature. The temperature—time curves of specimens and photographs can be watched on-line and recorded by a computer during the test. The results show that the totally 1mm-thick FG-TBCs have excellent thermal shock resistance due to the fact that the coatings have no any peeling-off after 200 thermal cycles. The microstructures and morphologies of FG-TBCs were characterized and analyzed by SEM.

Network pharmacological analysis on the active ingredients of Yigan Powder in treating Alzheimer's disease with depressive disorder

Objective:To study the potential therapeutic effect of Yigan Powder on Alzheimer’s disease(AD)comorbid Depressive Disorder with Network Pharmacology.Methods:The active ingredients of Yigan Powder were screened from Traditional Chinese Medicine Systems Pharmacology database and analysis platform(TCMSP)by ADME parameters,targets are predicted by Swiss Target Prediction database,disease targets are downloaded from GeneCards,OMIM and PharGKB database.Using R to run GO terms enrichment and KEGG pathway enrichment analysis.Protein interaction data is downloaded from the String database.Cytoscape software is used to build network.AutoDock Vina and PyMOL software are used for molecular docking.Results:There are 125 active ingredients in Yigan Powder with 953 predicted targets,85 of predicted targets are related to Alzheimer's Disease comorbid Depressive Disorder,shows highly enriched signaling pathways and biological processes.PPI network shows APP,MAPK1 and STAT3 may be important potential treatment of Alzheimer's Disease comorbid Depressive Disorder.The results of AutoDock Vina docking showed that the active ingredients of Yigan Powder had good binding activity with important receptors.Conclusion:Yigan Powder shows effect on neurotransmitter metabolism,synaptic transmission,neuroinflammation and other aspects in the treatment of Alzheimer's Disease comorbid Depressive Disorder.

粉末SBR-g-s的制备及其对PS的增韧作用

用凝聚法制备了粒径小于１ｍｍ的粉末ＳＢＲｇｓ。研究了粉末ＳＢＲｇｓ对ＰＳ的增韧效果。结果发现粉末ＳＢＲｇｓ与ＰＳ共混体的冲击强度与ＳＢＲｇｓ的交联程度、接枝率和组成比有关。当ＳＢＲｇｓ的溶胀指数为２４３，接枝率为２８１％，ＳＢＲ／ｇｓ的比率为６５／３５（质量）时对ＰＳ有良好的增韧效果。当这种粉末ＳＢＲｇｓ与ＰＳ的共混比为３５／６５（质量），其共混体的冲击强度可达４８５ｋＪ／ｍ２（无缺口）。

Effects of PVP K30 on Aqueous Solubility and Dissolution Propertiesof Daidzein

AimTo study effects of PVP K30 on the aque ou s solubility and dissolution properties of daidzein. Methods To measure the aqueous solubility and dissolution rates of daidzein in three diffe rent states (within solid dispersions, physical mixtures and as a pure drug) and investigate drug-polymer interactions in the solid state using X-ray powder d iffraction and fourier-transform infrared spectroscopy. Results The negative values of the Gibbs free energy and enthalpy of transfer explaine d the spontaneous transfer of daidzein from phosphate buffer solution (PBS) to a solution of PVP in PBS. X-ray powder diffraction patterns showed that the drug was in the amorphous state (ratio of the drug ∶ PVP<1∶5) when dispers ed i n PVP K30. The infrared spectra indicated there exist interactions between the O H of daidzein and the C=O of PVP K30. Conclusionthe dispersion of daidzein in PVP K30 considerably enhances the solubility and dissolution rat e.

富碳无定形SiC超微粉预氧化及高温脱碳脱氧结晶化工艺研究

对于含有大量残碳的无定形ＳｉＣ超微粉，采用预氧化，高温脱碳脱氧结晶化处理工艺可以制备出纯度较高的β－ＳｉＣ超微粉。在预氧化过程中，定量引入氧原子，使微粉中的残碳与氧的原子比接近理论比值１：１，然后在高温过程中使残碳与氧发生固相反应。探讨了实验条件下温度、气氛等反应条件对产物性质的影响，并对其反应机理进行了讨论。

水溶性新显色剂5-Br-PADN-S的制备与分析特性的研究及其用于锌的测定

报道了水溶性 １－（５－溴－２－吡啶偶氮）－２，７－萘二酚－６－磺酸（５－Ｂｒ－ＰＡＤＮ－Ｓ）的制备方法及其分析特性。研究了此试剂与锌（Ⅱ）等金属离子在水溶液中直接测定的显色反应，在ｐＨ １０．０～１１．４ 的Ｎａ２Ｂ４Ｏ７～ＮａＯＨ 缓冲溶液中，５－Ｂｒ－ＰＡＤＮ－Ｓ与锌（Ⅱ）形成２∶１ 的紫色配合物，最大吸收波长位于５４２ ｎｍ ，表观摩尔吸光系数ε５４２＝ ６．３８×１０４ Ｌ／（ｍ ｏｌ·ｃｍ ），锌量在０～２０ ｍ ｇ／１０ Ｌ范围内符合比耳定律。在掩蔽剂的存在下，用于人发、奶粉及矿石等试样中锌的测定，结果与ＡＡＳ法一致。

溶胶－凝胶法制备SiC－AIN复合超细粉末的研究

用溶胶－凝胶碳热氮化法在１５５０～１６５０℃，５０ｍｉｎ下制得平均粒径为０．２μｍ左右的ＳｉＣ－ＡＩＮ复合超细粉末，粉末烧结性能良好；在较低合成温度下（１５５０～１６００℃），粉末中出现晶须。本研究还探讨了粉末氨化合成条件对粉末颗粒及物相的影响。

PS/粉末SBR-g-S共混体研究Ⅱ.粉末SBR-g-S的相结构及其与PS的相容性

测定了 SBR- g- S的接枝率 ,用 TEM检测了粉末 SBR- g- S(PR)的相结构。用 DSC测定了 PS/ PR共混体的Tg,研究了 PS/ PR共混体的相容性。结果发现 ,在接枝率为 32 .6 %的粉末非交联 SBR- g- S(PR1 )的相结构中 SBR为连续相 ,在连续相中均匀分布着直径约 0 .0 1μm的 PS微区 ;PS为细胞状分散相 ,粒径 1～ 5μm,分散相含有SBR包藏物。在接枝率为 8.5 %的粉末交联 SBR- g- S(PR2 )的相结构中 PS为连续相 ,SBR为分散相 ,分散相粒径约0 .3μm。共混体 PS/ PR1 的相容性优于 PS/ PR2 。 SBR在 PS富相中有较高的含量是导致 PS/ PR1 共混体在冲击断裂时发生剪切屈服的主要原因。

S_(3307)乳剂和可湿性粉剂对稻苗的生理影响

Ｓ３３０７，稀效唑，英文名Ｕｎｉｃｏｎｚｏｌｅ，是８０年代初期由日本住友公司推出的三唑类新型的植物生长调节剂。它具有高效、低毒、低残留的特点，在农业生产上的应用有广阔的前景［１，２］。用Ｓ３３０７浸种，处理之后的稻苗表现为矮壮、根冠比增大、叶色深绿，...

负载茜素红S的纳米磁性碳粉修饰电极测定牛白蛋白

采用化学沉积法在纳米碳粉上合成磁性Fe3O4颗粒，纳米碳粉吸附茜素红S后通过磁力附着在石墨电极上，制成了负载茜素红S的纳米磁性碳粉修饰电极。研究了该电极在0．014mol／LH2SO4-0．2mol／LKCl溶液中对ARS-牛白蛋白的电还原作用，考察了多种实验条件对峰电流的影响。在-0．45V电位下，牛白蛋白浓度在1．5×10^-8～9×10^-7mol／L范围内与线性扫描伏安法还原电流成反比，从而实现对牛白蛋白的测定，并初步研究了电化学反应机理。此方法制成的磁性纳米颗粒修饰电极集分离、富集、测定和更新于一体，具有更新方便的特点。

BCL-100型催化剂在Innovene S工艺装置上实现长周期生产

通过国产BCL-100型催化剂取代进口催化剂的工业化试用,证明该催化剂可以在Innovene S工艺上进行长周期工业化生产。生产过程中装置运行平稳,第一聚合反应器在线取样器过滤器未出现堵塞,第二聚合反应器轴流泵的轴功率稳定,装置高压闪蒸排料系统运转正常,高压闪蒸过滤器压差正常。分析用两种催化剂生产的高密度聚乙烯(HDPE)粉料得出:与进口催化剂相比,用BCL-100型催化剂生产的HDPE细粉含量少、粒径较大,低聚物质量分数低约25%,第二聚合反应器中己烷抽提物中共聚单体质量分数低约27%。

湿化学法制备微晶（Y，Mg）－PSZ／MgAl_2O_4陶瓷的研究

研究了用湿化学法制备Ｙ_２Ｏ_３－ＭｇＯ－ＺｒＯ_２－Ａｌ_２Ｏ_３四元系超细粉末的工艺技术，探讨了包裹沉淀和包裹沉淀－乙酸镁混合两种制备工艺及组成对微晶ＰＳＺ材料结构、性能的影响。经１１００℃适当时间的热处理获得了在ｃ－ＺｒＯ_２中具有ｔ－ＺｒＯ_２梭形析出体的微晶ＰＳＺ复相陶瓷，其室温强度达８００ＭＰａ，断裂韧性在１４ＭＰａ·ｍ１／２左右，１０００℃下高温强度可达４５８ＭＰａ。

Si_3N_4超微粒的RF－CVD合成及其介电性质

利用自制的ＲＦ－ＣＶＤ装置合成了Ｓｉ_３Ｎ_４超微粒。着重考察了反应气混合方式对反应机理、化学含量、粒子形态及凝聚结构的影响。得到的Ｓｉ＿３Ｎ＿４粒子的典型尺寸为１０～５０ｎｍ，并且凝聚形成分形结构，其对应不同反应温度合成的粒子的分形维数约在２．１５到１．７４之间。非晶Ｓｉ＿３Ｎ＿４超微粒经１ＧＰａ高压压制，可看成是Ｓｉ＿３Ｎ＿４粒子和界面空隙组成的多相复合材料，它的异常介电性质能够用多相材料性质的逾渗理论得到解释。

PS/粉末SBR-g-s共混体的相结构与增韧效应

用ＴＥＭ、ＳＥＭ和ＤＳＣ分别检测了ＰＳ／粉末ＳＢＲｇｓ共混体的相结构、冲击断面形貌和相容性，讨论了共混体的相结构对冲击强度的影响。结果发现，能在共混体中形成分散相粒径为０７～１１μｍ，并与ＰＳ有良好相容性的粉末ＳＢＲｇｓ，对ＰＳ的增韧效果最好。

PS/粉末SBR-g-s共混体研究Ⅰ.相结构、冲击断裂机理与冲击韧性

以粉末 SBR- g- s与 PS树脂共混 ,测定了共混体的 Charpy无缺口冲击强度与 PR用量的关系曲线。用 TEM和 SEM分别分析了共混体的相结构和冲击断面形貌。研究了共混体的相结构、冲击断裂机理和冲击强度之间的关系。结果发现 ,在关系曲线被转变点划分的每一区域内 ,冲击断裂机理只发生量变而无质变 ,故冲击强度与 PR用量成正比 ,而随着区域的变换冲击断裂机理发生了质变 ,导致了冲击强度的变化不连续 ,从而出现转变点。当粉末非交联 SBR- g- s用量为 2 0 % ,共混体发生脆韧转变 ;其冲击断面局部区域呈“须根”形貌 ,证实存在剪切屈服机理 ;脆韧转变的临界条件为 :橡胶相粒径≥ 0 .8μm,粒面间距离≤ 0 .9μm,PS富相含混溶性 SBR( SBR/PS,质量 )≥ 3%。

不同工艺条件对马铃薯全粉中SO_2残留量的影响

二氧化硫残留量(RSD)是马铃薯颗粒全粉的重要品控指标之一。本实验显示,RSD与亚硫酸盐护色液浓度和护色时间均呈线性关系;与薯片蒸煮时间呈幂函数关系;与蒸煮温度呈二元函数关系。欲使马铃薯颗粒全粉RSD最低的蒸煮温度为104～105℃。

卒中散对脑出血大鼠抓握能力的改善及血清S100B水平的影响

目的:探讨卒中散对脑出血大鼠抓握能力的改善及血清S100B水平的影响,为其临床应用提供理论依据。方法:40只SD大鼠随机分成假手术组、手术组、卒中散组、脑复康组,参照Rosenberg法制作大鼠脑出血模型,造模第2天测定大鼠抓握能力,用ELISA法检测造模后24h及48h血清S100B水平。结果:(1)卒中散组大鼠抓握能力明显好于手术组,两者比较有显著差异(P<0.05)。(2)卒中散组大鼠血清S100B水平明显低于手术组,两者比较有显著差异(P<0.05)。结论:卒中散能明显改善脑出血大鼠抓握能力,降低血清S100B水平,具有神经保护作用。