垂直线生产的可锻铸铁管件缺陷改进措施

针对垂直线生产可锻铸铁管件出现的较严重的气孔、夹渣、缩松缺陷,分析缺陷产生原因,并通过优化浇注系统、排气方式及增设集渣包等改进措施实施,解决了可锻铸铁管件气孔、夹渣、缩松缺陷.     

硅对蠕墨铸铁热分析特征值及蠕化率的影响

试验设计了 5种不同硅含量的蠕墨铸铁铁液,分析了硅含量对蠕墨铸铁凝固的热分析曲线特征值TEU、TER、△Tr和蠕墨铸铁蠕化率的影响.试验结果表明:(1)在本次试验的硅含量范围内,蠕墨铸铁热分析曲线的特征值TEU和TER先是随着硅的增加而上升,然后,变化不明显;(2)蠕墨铸铁共晶温度回升特征值△Tr随着硅含量的增加呈下降...     

某铁矿井下多工作面协同爆破智能管控体系研究

基于某铁矿穿孔和爆破工序分割、多中段多工作面同时作业的工程背景,采用跟踪调研的方法得出该铁矿具有爆破作业管控难度大、工序反馈衔接不及时、有效作业人员占比小等问题。以解决上述难题为目的,采用工序分析、问题提出、风险评估等层层递进的方法,开展井下多工作面协同爆破智能管控体系研究,其结果表明：井下爆破作业各工序间具有严谨的先后顺序;爆破器材运输和装药工序的危险程度最高,需精准管控;采用智能软件协同监管多工作面爆破作业工序,不仅精准管控效率高,还可降低矿山爆破作业的事故机率。最后结合某铁矿的实际作业条件,基于多工作面同时爆破作业的先后流程,采用Python语言开发了井下多工作面协同爆破智能管控软件,并通过爆破作业工作面的管理调试,证明研发的管控软件适合辅助该铁矿爆破工序的监管。     

pH值对溶胶-凝胶法制备纳米TiO2的影响

利用溶胶-凝胶法制备了纳米TiO2颗粒,采用透射电镜(TEM)和X射线衍射(XRD)对产物进行了表征,考察了Ti4+-三乙醇胺(Ti-TEOA)络合体系组成随陈化时间的变化及pH对TiO2粒径、结晶习性、产率及Ti-TEOA稳定性的影响. 结果表明,产物为锐钛型TiO2,140℃陈化时,Ti(OH)4凝胶在10 h后全部转化为TiO2颗粒,平均粒径5~22 nm;随pH升高,粒径增大,但TiO2产率在pH>10.6时显著下降,至pH 12时无TiO2颗粒生成;不同pH时TiO2结晶习性变化明显. 25℃下pH>6时Ti-TEOA络合体系稳定.     

改进固相法制备LiFePO4/C正极材料及其性能

采用改进的固相反应法制备了掺碳的磷酸铁锂正极材料,并用XRD,SEM,元素分析,红外光谱及激光粒度分布仪等对样品进行了测试分析.结果表明,样品具有单一的橄榄石结构和较好的放电平台(约3.4V),粒度较小粒径分布均匀,0.1C首次放电比容量为137.8mAh/g,循环20次后容量保持率为92.6%,以1C倍率首次放电比容量为129.6mAh/g,循环20次后容量下降10.8%.     

Multi-scale mechanistic modelling of the host defence in invasive aspergillosis reveals leucocyte activation and iron acquisition as drivers of infection outcome

Aspergillus species are ubiquitous environmental moulds, with spores inhaled daily by most humans. Immunocompromised hosts can develop an invasive infection resulting in high mortality. There is, therefore, a pressing need for host-centric therapeutics for this infection. To address it, we created a multi-scale computational model of the infection, focused on its interaction with the innate immune system and iron, a critical nutrient for the pathogen. The model, parameterized using published data, was found to recapitulate a wide range of biological features and was experimentally validated in vivo. Conidial swelling was identified as critical in fungal strains with high growth, whereas the siderophore secretion rate seems to be an essential prerequisite for the establishment of the infection in low-growth strains. In immunocompetent hosts, high growth, high swelling probability and impaired leucocyte activation lead to a high conidial germination rate. Similarly, in neutropenic hosts, high fungal growth was achieved through synergy between high growth rate, high swelling probability, slow leucocyte activation and high siderophore secretion. In summary, the model reveals a small set of parameters related to fungal growth, iron acquisition and leucocyte activation as critical determinants of the fate of the infection.     

Application of functionalized magnetic silica nanoparticles for selective induction of three coumarin metastable polymorphs

The precise control of active pharmaceutical ingredient(API) crystal nucleation and polymorphism is a key consideration in pharmaceutical manufacturing.In this study,tunable nanoparticles were developed to regulate the nucleation process of coumarin.Magnetic silica nanoparticles with four different functional groups(-NH₂,-COOH,-SH,-NCO) were prepared and coated on the substrate for inducing the crystallization of coumarin.Confined melt crystallization and microspacing sublimation crys...     

Fe3O4-carbon spheres core–shell supported palladium nanoparticles:A robust and recyclable catalyst for suzuki coupling reaction

Suzuki-Miyaura(S-M) is regarded the most powerful way for synthesis biaryls, triaryls, or incorporating of substituted aryl moieties in organic preparation by the cross-coupling of aryl boronic acid with aryl halides using the Pd catalyst. This work reports the combining of the hydrothermal and microwaveassisted protocol to convert the glucose to magnetic carbon spheres(Fe₃O₄-CSPs) decorated with Pd nanoparticles(NPs) as the catalyst for Suzuki-Miyaura cross-coupling reacti...     

Modulatory Effects of Biosynthesized Gold Nanoparticles Conjugated with Curcumin and Paclitaxel on Tumorigenesis and Metastatic Pathways—In Vitro and In Vivo Studies

Background: Breast cancer is the most common cancer in women globally, and diagnosing it early and finding potential drug candidates against multi-drug resistant metastatic breast cancers provide the possibilities of better treatment and extending life. Methods: The current study aimed to evaluate the synergistic anti-metastatic activity of Curcumin (Cur) and Paclitaxel (Pacli) individually, the combination of Curcumin–Paclitaxel (CP), and also in conjugation with gold nanoparticles (AuNP–Curcumin (Au-C), AuNP–Paclitaxel (Au-P), and AuNP–Curcumin–Paclitaxel (Au-CP)) in various in vitro and in vivo models. Results: The results from combination treatments of CP and Au-CP demonstrated excellent synergistic cytotoxic effects in triple-negative breast cancer cell lines (MDA MB 231 and 4T1) in in vitro and in vivo mouse models. Detailed mechanistic studies were performed that reveal that the anti-cancer effects were associated with the downregulation of the expression of VEGF, CYCLIN-D1, and STAT-3 genes and upregulation of the apoptotic Caspase-9 gene. The group of mice that received CP combination therapy (with and without gold nanoparticles) showed a significant reduction in the size of tumor when compared to the Pacli alone treatment and control groups. Conclusions: Together, the results suggest that the delivery of gold conjugated Au-CP formulations may help in modulating the outcomes of chemotherapy. The present study is well supported with observations from cell-based assays, molecular and histopathological analyses.