Stimulating Biological Nitrification via Electrolytic Oxygenation

The feasibility of electric current prompted aerobic biodegradation of NH4+–N in an attached growth bioreactor system is demonstrated. Nitrification was induced at electric current densities of 1.25 and 2.5?mA/cm2 and with pure oxygen supplied at a rate equivalent to 1.25?mA/cm2 when the bioreactor was operated in batch mode at 6 days detention time. About 84% (27?mg/L)?NH4+–N loss was observed at the end of each detention period during all three experimental conditions, indicating that the electric current did not negatively impact the rate of nitrification. Nitrite accumulation was observed during the initial stages of nitrification experiments with 1.25?mA/cm2 current intensity, but nitrite did not accumulate during the other two sets of nitrification experiments. A mathematical model formulated to obtain the rates of biological reactions showed that rates of NH4+–N removal are similar for all aeration conditions. Abiotic experiments showed that NH4+–N was not removed electrolytically and via stripping, confirming that NH4+–N disappearance is due to biological activity.     

A simple method for the evaluation of fracture toughness of a multi-layered laminate based on the failure stress of sub-laminates

A simple analytical method is presented that can be used to predict the intralaminar fracture toughness of multilayered composite laminate based on the failure stresses of its sub laminates. MCCI approach is followed to verify the fracture toughness of a base laminate and the method is validated comparing the available test data on the toughness value of the base laminate with the prediction. It is observed that a better representation of carbon —epoxy base laminate by its sub laminate gives very good agreement in prediction within 3%.     

锂离子电池电解质盐双草酸硼酸锂的研究进展

介绍了双草酸硼酸锂(LiBOB)的基本性质,综述了LiBOB合成方法和应用情况,并对LiBOB与石墨负极匹配、高温稳定性、在溶剂中的溶解性、电导率和安全性等问题进行了论述,对研究方向也进行了简单的阐述。     

预浸水法消除大厚度自重湿陷性黄土地基研究

为了在大厚度自重湿陷性场地建筑水利工程，基本消除黄土的湿陷性，通过在宁夏固海扩灌十一泵站场地进行预浸水的试验研究，观测了湿陷量与浸水时间关系、耗水量与浸水时间关系、场地变形量，以及处理效果检测与评价，得出大厚度自重湿陷性黄土场地经过一定的预浸水后，黄土自重湿陷量全部消除．地基呈中压缩性，承栽力特征值为150kPa的结论．为同类工程建设提供可以借鉴的经验．     

Oxidation behaviour of the near α-titanium alloy IMI 834

Oxidation behaviour of the near α-titanium alloy IMI 834 was investigated over a range of temperatures, from 600–800°C, in air. Specimens were solution-treated in the α + β and β phase fields for 1 h and 1/2 h, respectively and cooled in air to room temperature. The solution treated samples were subjected to stabilization treatment at 700°C for 2 h, followed by cooling in air. Oxidation behaviour of these samples was studied from 600–800°C in air, for 50 h. The morphology of the scales formed was examined by SEM and the phases present in the scales were characterized by X-ray diffraction. While there was little oxidation at 600°C, the rate of oxidation increased at higher temperatures. In general, the rate of oxidation was found to be more in the α + β treated condition than that in the β treated one. The results are discussed in terms of the characteristics of the oxide film formed under different conditions.     

基于MC13233的ZigBee物理层分析与设计

以Freesacle公司的ZigBee RF4CE芯片MC13233为基础,依据嵌入式硬件构件的规范设计了硬件各模块。介绍MC13233的ZigBee物理层的模型。详细阐述MC13233的ZigBee物理层的设计方法,具体实现RF收发器的工作模式设置、物理层数据收发、CCA/ED/LQI,并给出了物理层正确性和可靠性测试。     

Investigation on microstructure and tensile behaviour of stir cast LM13 aluminium alloy reinforced with copper coated short steel fibers using response surface methodology

Copper coated steel fibers reinforced LM13 aluminium alloy composites have been prepared using stir casting process. Experiments have been designed using response surface methodology by varying wt% of reinforcement (0–10), stirrer speed (350–800 rpm) and pouring temperature (700–800 °C). Microstructure, tensile strength and fracture surface of composites have been investigated. Analysis of variance, significance test and confirmation tests have been performed and regressions models have been developed to predict the tensile strength of composites. Response surface plots reveal that tensile strength of composites increases with increasing wt% of copper coated steel fibers reinforcement up to 6 wt%. Further increase in wt% of steel fibers decreases the tensile strength of composites. However tensile strength of composites increases with increasing stirrer speed due to the uniform and homogeneous dispersion of steel fibers in matrix. Optimum stir cast process parameters for obtaining higher tensile strength are found to be 5.9 wt% of reinforcement, 753 °C pouring temperature and stirrer speed of 633 rpm. Fracture mechanism is dominated by steel fiber pullouts in composites with higher wt% of reinforcement and dimples are observed in the surface of composites containing lower levels of wt% of reinforcement.     

基于系统化的老旧小区海绵化改造工程精细化设计案例

在青岛市湖畔雅居和石沟社区老旧小区海绵化改造工程中,对当地集中短历时强降雨的气象条件,丘陵地形起伏大、局部易积水的地形以及地下水位低、土壤渗透性好的地质等特点进行了精细化分析,对径流控制、污染物负荷削减、管网排放能力、山洪控制、雨水利用、内涝防治等进行了精细化计算与设计,同时引入"微分区"概念精细化校核各LID及所在的微分区的蓄水能力与实际蓄水量,实行串联转输流量、相邻分区消纳,以避免出现低效率甚至无效率的海绵设施,系统地将保障水安全、改善水环境、修复水生态、涵养水资源、提升水景观结合为一个整体,并强化设计"渗、蓄、排"的透水混凝土路面、雨水调蓄池、旱溪、砾石沟等海绵措施,配置了耐旱、耐湿、耐阴、耐污染而且科学、生态、富有观赏性的植物。基于精细化设计,该工程实际运行效果良好。     

Ligand-Specific Nano-Contrast Agents Promote Enhanced Breast Cancer CT Detection at 0.5 mg Au

For many cancer types, being undetectable from early symptoms or blood tests, or often detected at late stages, medical imaging emerges as the most efficient tool for cancer screening. MRI, ultrasound, X-rays (mammography), and X-ray CT (CT) are currently used in hospitals with variable costs. Diagnostic materials that can detect breast tumors through molecular recognition and amplify the signal at the targeting site in combination with state-of-the-art CT techniques, such as dual-energy CT, could lead to a more precise detection and assist significantly in image-guided intervention. Herein, we have developed a ligand-specific X-ray contrast agent that recognizes α5β1 integrins overexpressed in MDA-MB-231 breast cancer cells for detection of triple (−) cancer, which proliferates very aggressively. In vitro studies show binding and internalization of our nanoprobes within those cells, towards uncoated nanoparticles (NPs) and saline. In vivo studies show high retention of ~3 nm ligand-PEG-S-AuNPs in breast tumors in mice (up to 21 days) and pronounced CT detection, with statistical significance from saline and iohexol, though only 0.5 mg of metal were utilized. In addition, accumulation of ligand-specific NPs is shown in tumors with minimal presence in other organs, relative to controls. The prolonged, low-metal, NP-enhanced spectral-CT detection of triple (−) breast cancer could lead to breakthrough advances in X-ray cancer diagnostics, nanotechnology, and medicine.     

MicroRNAs as Potential Biomarkers in the Differential Diagnosis of Lipomatous Tumors and Their Mimics

Adipocytic tumors are the most common subtype of soft tissue tumors. In current clinical practice, distinguishing benign lipomas from well-differentiated liposarcomas (WDLPS), as well as dedifferentiated liposarcomas (DDLPS) from their morphologic mimics, remains a significant diagnostic challenge. This is especially so when examining small biopsy samples and without the aid of additional ancillary tests. Recognizing the important role that microRNAs (miRNAs) play in tumorigenesis and their potential utility in tumor classification, we analyzed routine clinical tissue samples of benign and malignant lipomatous tumors, as well as other sarcoma mimics, to identify distinguishing miRNA-based signatures that can aid in the differential diagnosis of these entities. We discovered a 6-miRNA signature that separated lipomas from WDLPS with high confidence (AUC of 0.963), as well as a separate 6-miRNA signature that distinguished DDLPS from their more aggressive histologic mimics (AUC of 0.740). Functional enrichment analysis unveiled possible mechanistic involvement of these predictive miRNAs in adipocytic cancer-related biological processes and pathways such as PI3K/AKT/mTOR and MAPK signaling, further supporting the relevance of these miRNAs as biomarkers for adipocytic tumors. Our results demonstrate that miRNA expression profiling may potentially be used as an adjunctive tool for the diagnosis of benign and malignant adipocytic tumors. Further validation studies are warranted.