粉体含能材料生产与储运中的静电安全及防护

分析了静电产生的原因,阐述了粉体含能材料生产中的静电起电现象、静电的危害、静电安全性评估标准以及建立在此标准基础上的静电放电危险的评价办法,提出了粉体含能材料在生产、运输中所需要采取的静电防护措施。     

Authenticity green coffee bean species and geographical origin using near-infrared spectroscopy combined with chemometrics

To prevent the adulteration of agricultural resources and provide a solution to enhance the green coffee bean supply chain, authentication using the near-infrared spectroscopy (NIRS) technique was investigated. Partial least square with discrimination analysis (PLS-DA) models combined with various preprocessing methods were built from NIR spectra of 153 Vietnamese green coffee samples. The model combined with the standard normal variate and the first order of derivative yielded excellent performance in predicting coffee species with the error cross-validation of 0.0261. PLS-DA model of mean centre and first-order derivative spectra also yielded good performance in verifying geographical indication of green coffee with the error of 0.0656. By contrast, the predicting abilities of post-harvest methods were poor. The overall results showed a high potential of the NIRS in online authentication practices.     

Green Measurements for Software Product Based on Sustainability Dimensions

Software is a central component in the modern world and vastly affects the environment’s sustainability. The demand for energy and resource requirements is rising when producing hardware and software units. Literature study reveals that many studies focused on green hardware; however, limited efforts were made in the greenness of software products. Green software products are necessary to solve the issues and problems related to the long-term use of software, especially from a sustainability perspective. Without a proper mechanism for measuring the greenness of a particular software product executed in a specific environment, the mentioned benefits will not be attained. Currently, there are not enough works to address this problem, and the green status of software products is uncertain and unsure. This paper aims to identify the green measurements based on sustainable dimensions in a software product. The second objective is to reveal the relationships between the elements and measurements through empirical study. The study is conducted in two phases. The first phase is the theoretical phase, where the main components, measurements and practices that influence the sustainability of a software product are identified. The second phase is the empirical study that involved 103 respondents in Malaysia investigating current practices of green software in the industrial environment and further identifying the main sustainability dimensions and measurements and their impact on achieving green software products. This study has revealed seven green measurements of software product: Productivity, Usability, Cost Reduction, Employee Support, Energy Efficiency, Resource Efficiency and Tool Support. The relationships are statistically significant, with a significance level of less than 0.01 (p = 0.000). Thus, the hypothesised relationships were all accepted. The contributions of this study revolve around the research perspectives of the measurements to attain a green software product.     

Photocatalytic performance of β-Ga2O3 microcubes towards efficient degradation of malachite green

In this work, the photocatalytic degradation of malachite green (MG) solutions by β-Ga₂O₃ was investigated. The latter was synthetized by reacting gallium nitrate with concentrated formic acid, which produced gallium formate. The thermal decomposition of this compound at 850 °C produced single-phase β-Ga₂O₃. The resulting morphology corresponds to non-agglomerated microcubes, with a size in the range of 0.8 and 2.3 μm. The surface chemical composition and bandgap energy of this oxide were determined by X-ray photoelectron spectroscopy (XPS) and the Tauc method, respectively. The photodegradation of MG was carried out under violet light (λ = 405 nm), at room temperature, using the as-prepared powder. The results revealed a fast degradation of the dye during the first 20 min, which attenuates over time. The rate of photodegradation depends on the amount of β-Ga₂O₃ used and can be fitted by an exponential equation. The role of free hydroxyl radicals and reactive oxygen species in photocatalysis was addressed by using analytic techniques (FTIR and XPS).     

Contribution of Drugs Interfering with Protein and Cell Wall Synthesis to the Persistence of Pseudomonas aeruginosa Biofilms: An In Vitro Model

The occurrence of Pseudomonas aeruginosa (PA) persisters, including viable but non-culturable (VBNC) forms, subpopulations of tolerant cells that can survive high antibiotic doses, is the main reason for PA lung infections failed eradication and recurrence in Cystic Fibrosis (CF) patients, subjected to life-long, cyclic antibiotic treatments. In this paper, we investigated the role of subinhibitory concentrations of different anti-pseudomonas antibiotics in the maintenance of persistent (including VBNC) PA cells in in vitro biofilms. Persisters were firstly selected by exposure to high doses of antibiotics and their abundance over time evaluated, using a combination of cultural, qPCR and flow cytometry assays. Two engineered GFP-producing PA strains were used. The obtained results demonstrated a major involvement of tobramycin and bacterial cell wall-targeting antibiotics in the resilience to starvation of VBNC forms, while the presence of ciprofloxacin and ceftazidime/avibactam lead to their complete loss. Moreover, a positive correlation between tobramycin exposure, biofilm production and c-di-GMP levels was observed. The presented data could allow a deeper understanding of bacterial population dynamics during the treatment of recurrent PA infections and provide a reliable evaluation of the real efficacy of the antibiotic treatments against the bacterial population within the CF lung.     

低共熔溶剂用于CO2捕集的研究进展

低共熔溶剂(DESs)具有原料廉价易得、化学稳定性好、可设计、合成工艺简单、可循环使用和绿色环保等优点,在CO₂捕集领域受到广泛关注。重点综述了近年来DESs用于CO₂捕集的研究进展,总结了DESs捕集CO₂的能力,分析了DESs捕集CO₂的影响因素和DESs的循环使用性能,归纳了DESs捕集CO₂的机理(包括物理吸收、化学吸收和物理化学协同吸收),并总结了CO₂在DESs中的溶解度计算模型。分析发现,DESs捕集CO₂的影响因素中,温度、压力和水含量(质量分数)均对CO₂的捕集有影响,且DESs的结构是重要的影响因素;大部分DESs可循环使用;CO₂在DESs中溶解度计算模型的建立有效推动了DESs捕集CO₂的进一步发展。最后,指出了DESs捕集分离CO₂所面临的主要问题并对进一步的研究工作进行了分析讨论。     

臭氧氧化技术在有色金属湿法冶金中的应用研究进展

臭氧是一种氧化性极强、多功能化的绿色氧化剂。本文综述了臭氧氧化技术在有色金属湿法冶金领域的研究进展和应用现状,重点介绍了在贵金属、重金属、稀有金属及轻金属等有色金属湿法冶金领域的应用研究。详细探讨了臭氧的强氧化性对低品位金属矿和难冶金属矿浸出、溶液中低价态金属离子氧化沉淀、溶液净化除杂等方面的作用机理,并对目前面临的问题进行简要叙述,对其在有色金属湿法冶金领域的应用前景进行了展望。     

2019年黑龙江省猪肉市场运行情况分析

2018年非洲猪瘟疫情出现以来,全国及黑龙江省生猪生产、猪肉市场受到了较大的影响,生猪、能繁母猪存栏减少,生猪出场价格也经历了明显波动。2019年春节以后,随着省外调出量增加和猪源减少,黑龙江省生猪出场价格进入上升通道,超过了全国平均水平,白条猪肉批发价格和猪肉市场零售价格随之上行。通过对2019年黑龙江省生猪生产环节、屠宰加工环节、猪肉市场零售环节进行调研,对生猪出场价格、白条猪肉批发价格、猪肉零售价格、生猪和能繁母猪产能等指标进行分析,阐述了以生猪和猪肉市场为重点的肉类产销形势,为促进肉类产业高质量发展、提高市场保供能力提供参考。