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Symmetrical multi-inlet vortex separators/reactors have been demonstrated to be beneficial for gas-particle separation and mass transfer, but their internal energy dissipation has remained unknown. This work designed a series of microscale vortex separators/reactors with single-, dual-, and quadruple inlet(s), to conduct a comparative investigation on their energy-loss characteristics and nature. The response of energy loss to inlet configuration and flow rate was experimentally determined. It is found that in 30–100 L/min flow rate, the Euler number depends insignificantly upon the Reynolds number. The introduction of the multi-inlets improves the symmetry of the flow pattern but increases the gradients of vortex velocity and static pressure. RSM-based CFD simulation can effectively reveal the effect of multiple inlets on the inside flow, static pressure, and energy-loss composition. Finally, an improved semi-empirical correlation of energy loss was developed. The results may provide a positive reference for the design, optimization, and application of vortex-based separators/reactors.

The potential for mitigating climate change is growing worldwide, with an increasing emphasis on reducing CO2 emissions and minimising the impact on the environment. African continent is faced with the unique challenge of climate change whilst coping with extreme poverty, explosive population growth and economic difficulties. CO2 emission patterns in Africa are analysed in this study to understand primary CO2 sources and underlying driving forces further. Data are examined using gravity model, logarithmic mean divisia index and Tapio's decoupling indicator of CO2 emissions from economic development in 20 selected African countries during 1984-2014. Results reveal that CO2 emissions increased by 2.11% (453.73 million ton) over the research period. Gravity centre for African CO2 emissions had shifted towards the northeast direction. Population and economic growth were primary driving forces of CO2 emissions. Industrial structure and emission efficiency effects partially offset the growth of CO2 emissions. The economic growth effect was an offset factor in central African countries and Zimbabwe due to political instability and economic mismanagement. Industrial structure and emission efficiency were insufficient to decouple economic development from CO2 emissions and relieve the pressure of population explosion on CO2 emissions in Africa. Thus, future efforts in reducing CO2 emissions should focus on scale-up energy-efficient technologies, renewable energy update, emission pricing and long-term green development towards sustainable development goals by 2030.

The purpose of this study was to analyze the influence of the injection pressure and orifice diameter on the spray characteristics of soybean biodiesel. The macroscopic spray characteristics of the spray tip penetration (STP) and spray cone angle (SCA) were tested with a high-speed camera system. The microscopic spray characteristics, such as the statistical size distribution, Sauter mean diameter (SMD), representative diameters and dispersion boundary, were obtained using a Malvern laser particle size analyzer (PSA). The test results showed that with an increasing injection pressure, the STP and the SCA of the biodiesel increased, but the curves of size-volume distribution and cumulative volume distribution of the atomized droplets shifted to smaller diameters. The SMD and representative diameters decreased, and the dispersion boundary was reduced. Moreover, with a decreasing orifice diameter, longer STP and smaller SCA values were observed. Similarly, the size distribution curves of the atomized biodiesel droplets shifted to smaller diameters. The SMD and representative diameters were reduced, and the relative size range of the atomized biodiesel droplets was enlarged. Higher injection pressures and smaller orifice diameters improved the biodiesel atomization; however, the smaller orifice diameters caused an inhomogeneous size distribution of the atomized biodiesel droplets.

Summary Background Stroke is a leading cause of death and disability worldwide. Despite considerable improvements in diagnosis and treatment, little is known about the short-term and long-term prognosis after a first stroke in low-income and middle-income countries, including China. We aimed to assess the short-term and long-term risk of recurrent stroke and mortality after a first stroke for each of the major pathological stroke types. Methods This population-based cohort study included adults aged 35–74 years without disability who were recruited to the China Kadoorie Biobank (CKB). A baseline survey was conducted in ten geographical areas (five urban, five rural) in China, and participants had clinical measurements recorded. Participants were followed up by monitoring death registries and by electronic linkage to health registries and health insurance claims databases, with follow-up until Jan 1, 2017. Participants were excluded from analyses if they had a previous history of stroke, transient ischaemic attack, or ischaemic heart disease at baseline. All incidences of fatal and non-fatal stroke during the study period were recorded by type (ischaemic stroke, intracerebral haemorrhage, subarachnoid haemorrhage, and unspecified type). Primary outcome measures were 28-day mortality, recurrent stroke, major vascular events (recurrent stroke, myocardial infarction, or vascular death), vascular mortality, and all-cause mortality. Findings Of 512 715 individuals in the CKB, 489 586 participants without previous ischaemic heart disease and stroke at recruitment were included, of whom 45 732 (42 073 [92%] confirmed by brain imaging) had a stroke during the study period. The mean age was 59·3 years (SD 9·8) for participants who had a stroke (54% women) and 50·8 years (10·3) for participants with no stroke (60% women). 36 588 (80%) of the incident cases of stroke were ischaemic stroke, 7440 (16%) were intracerebral haemorrhage, 702 (2%) were subarachnoid haemorrhage, and 1002 (2%) were an unspecified stroke type. 28-day mortality was 3% (95% CI 3–4) for ischaemic stroke, 47% (46–48)for intracerebral haemorrhage, 19% (17–22; 52% for rural areas and 32% for urban areas) subarachnoid haemorrhage, and 24% (22–27) for unspecified stroke. Among participants who survived stroke at 28 days, 41% (41–42) had recurrent stroke at 5 years (ischaemic stroke 41% [41–42], intracerebral haemorrhage 44% [42–46], subarachnoid haemorrhage 22% [18–27], unspecified stroke type 40% [35–44]) and mortality at 5 years was 17% ([17–18] ischaemic stroke 16% [15–16], intracerebral haemorrhage 28% [26–29], subarachnoid haemorrhage 16% [12–20], unspecified stroke type 15% [12–19]). After a first ischaemic stroke, 91% of recurrent strokes were also ischaemic stroke; after an intracerebral haemorrhage, 56% of recurrent strokes were intracerebral haemorrhage, and 41% of recurrent strokes were ischaemic stroke. Interpretation After a first stroke, the risk of recurrence or death within 5 years was high among this population of Chinese adults. Urgent improvements to secondary prevention of stroke in China are needed to reduce these risks. Funding Wellcome Trust, Medical Research Council, British Heart Foundation, Cancer Research UK, Kadoorie Charitable Foundation, Chinese Ministry of Science and Technology, National Natural Science Foundation of China. Copyright © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.

To investigate the clinical efficacy and safety of polaprezinc compared with rebamipide in the treatment of gastric ulcers (GU).GU patients (n = 224) from 10 clinical centers were prospectively enrolled and randomly divided into a control (n = 113) or test (n = 111) group. The control group was treated with rebamipide tablets, while the test group was treated with polaprezinc. The primary endpoint was the effective treatment rate, which was confirmed by gastroscopy after 8 weeks of treatment. The secondary efficacy endpoint was the improvement rate of gastrointestinal symptoms after 4 and 8 weeks of treatment.The basic characteristics of the two groups were well balanced. For the primary efficacy endpoint, the effective rates confirmed by gastroscopy, after treatment for the test and control groups were 81.48% and 74.31% (P = 0.1557), respectively. After 4 and 8 weeks of treatments, both treatment groups had comparable improvements rates in gastrointestinal symptoms (test vs. control: 44.44% vs. 39.45% [P = 0.4559] and 81.48% vs. 77.06% [P = 0.4223]). Further, the two groups had similar adverse events and reactions to the study drugs.These findings suggest that the efficacy and safety of polaprezinc were similar to those of rebamipide in the treatment of GU.

A general framework for the analysis of the urban water-energy nexus (WEN) was proposed and a dynamic and quantitative WEN model was developed based on the Long-range Energy Alternatives Planning System (LEAP) and Water Evaluation and Planning (WEAP) tools. Using Xiamen, China, as a case study, eleven future scenarios were designed to explore the impacts of different factors, from both supply and demand sides, on urban WEN. Both water-related energy (WRE) and energy-related water (ERW) were studied to reveal the interconnected relationship between water and energy. We found that most WRE and ERW savings lie on the supply side, except for demand management scenarios, and most scenarios have larger trans-boundary effects than in-boundary effects due to the import of large quantities of energy and water. Industry structure adjustments (oriented toward energy or water savings) and energy-saving measures have better co-benefits in terms of energy and water savings than other measures. Promoting electric vehicles increases electricity imports and related trans-boundary ERW. Such effects should be considered before importing resources from outside city boundaries. Developing high-tech industries might also increase energy or water burdens. Finally, the boundaries of urban WEN research were discussed to promote additional comparable studies.

Due to the impacts of globe climate change and human activities, dramatic variations in runoff and sediment load were observed for the Yellow River. Analyses of nearly 65 years’ data measured at main hydrologic-stations on the Yellow River from 1950 to 2014 indicated that, except for the Tangnaihai station in the head region, sharp downward trends existed in both the annual runoff and annual sediment load according to the Mann–Kendal trend test; and their abrupt changes occurred in 1986 and in 1980, respectively, according to the rank sum test. Factors affecting the changes in the runoff and sediment load were very complicated. Results indicated that the reducing precipitation and the increasing water consumption were the main causes for the runoff decline, while the impoundment of the Longyangxia Reservoir and its combined operation with the Liujiaxia Reservoir exerted a direct bearing on the abrupt change in the annual runoff. In addition to the sediment load decrease associated with the runoff reduction, the reduced storm intensity, the conducted soil erosion control, and the constructed dam buildings all played an important role in the trends and abrupt changes of sediment load decline.

The rapid development of China’s high-speed rail (HSR) has caused great concern worldwide, and its various environmental impacts is also a main topic. As such, a comprehensive assessment of these environmental impacts is significant for future HSR construction. In this study, a hybrid input-output life cycle method is applied to evaluate multi-footprints of Beijing-Tianjin intercity HSR, namely, carbon, water, land, and material footprints. Results show that the total carbon, water, land, and material footprints of the entire Beijing-Tianjin HSR construction are 3669.0 kt CO2, 54954.7 kt fresh water, 45830.6 ha land, and 8474.2 kt original materials. In the construction stage, bridge and rail systems have the largest environmental impacts, totally contributing above 74% of the four footprints. The indirect footprints from upstream material production have the dominant effects, accounting over 89% in the four footprints. Metal smelting and rolling, transportation equipment manufacturing, and non-metallic mineral products are high-water-consuming and high-emission sectors in raw material production. Improving industrial production efficiency, optimizing line layout, optimizing production distribution and construction process management are key mitigation ways for multi-footprints.

We previously reported the development of PE38KDEL-loaded anti-HER2 poly(lactic-co-glycolic acid) (PLGA) nanoparticles that bind and internalize in HER2-overexpressing breast cancer cells, enabling potent anti-tumor activity. To overcome the problems associated with the short half-lives of this drug delivery system, we have constructed PE38KDEL-loaded anti-HER2 PEGylated liposomes (PE-HER-liposomes). PE-HER-liposomes were constructed with Fab′ of recombinant humanized anti-HER2 monoclonal antibody (anti-HER2 Fab′) covalently linked to PEGylated liposomes containing PE38KDEL (PE-liposomes). We attached anti-HER2 Fab′ to the terminus of PEG (polyethylene glycol) on PEGylated liposomes. Incorporation of pyridylthiopropionoylamino-PEG-distearoylphosphatidylethanolamine (PDP-PEG-DSPE) into PEGylated liposomes followed by mild thiolysis of the PDP groups resulted in the formation of reactive thiol groups at the periphery of the liposomes. Efficient attachment of maleimide-derivatized anti-HER2 Fab′ took place under mild conditions. The characterization of PE-HER-liposomes, such as particle size, was evaluated by dynamic light-scattering detector. The Micro BCA method was used to determine the encapsulation efficiency of PE38KDEL and the quantity of conjugated Fab′. Flow cytometry and confocal microscopy showed that PE-HER-liposomes possessed receptor-specific binding and internalization for HER2-overexpressing SK-BR3 cells. Remarkably, PE-HER-liposomes were more cytotoxic than non-targeted PE-liposomes in HER2-overexpressing breast cancer cells. In conclusion, PE-HER-liposomes could serve as a promising therapeutic candidate for the treatment of HER2-overexpressing breast cancers.

A chemically modified electrode (CME) constructed by adsorption of aquocobalamin (VB12a) onto a glassy carbon electrode surface was demonstrated to catalyze the electro-oxidation of cysteine, a sulfhydryl-containing compound. The sulfhydryl oxidation occurred at 0.54-0.88 V vs. Ag AgCl depending on pH value (3.0-10.0). The electrocatalytic behavior of cysteine is elucidated with respect to solution pH, operating potential and other variables as well as the CME preparation conditions. When used as the sensing electrode in flow injection amperometric detection, the CME permitted detection of the compound at 0.8 V. The detection limit was 1.7 pmol. The linear response range went up to 1.16 nmol. The stability of the CME was shown by RSD (4.2%) over 10 repeated injections.

A wall-jet cell/carbon fibre microelectrode detector was designed and used for the micellar liquid chromatographic assay of acetaminophen. The separations were carried out in an analytical column packed with C-18 stationary phase and the mobile phase was

A novel wall-jet cell with parallel dual cylinder (PDC) microelectrodes was constructed and used for flow injection analysis (FLA). The detector takes the advantages of ''redox recycling'' between bipotentiostated microcylinder electrodes (- 0.4 V/SCE an

Dicyanobis(1,10-phenanthroline)iron(II)-modified glassy carbon electrodes were shown to exhibit an electrocatalytic response for the oxidation of acetaminophen with a decrease of 100 mV in the potential required. It can also inhibit the oxidation of ascorbic acid and uric acid. When used for amperometric monitoring of acetaminophen in a flowing stream, the coated electrode may permit detection at lower potentials compared with the naked surface. The method gives a linear range from 0.05 to 100 μg ml −1 and a detection limit of 0.02 μg ml −1 (signal-to-noise ratio = 2). The application of the method to the determination of acetaminophen in urine by LC is briefly described.

A stable indium ferricyanide-modified glassy carbon electrode (InHCF/GCE-2) was prepared and exhibited excellent electrocatalytic activity in the oxidation of reduced glutathione (GSH) in acidic media. Liquid chromatography with electrochemical detection (LCEC), incorporating the InHCF/GCE-2, has been employed for the determination of normal circulating levels of GSH in human plasma. The mobile phase consisted of 0.1 mol/liter phosphate butler (pH 3.0) containing 50 μmol/liter ethylenediaminetetraacetic acid (EDTA). A linear range was over two orders of magnitude. The limit of detection for GSH was 1.6 μmol/liter. The mean recovery of GSH added to the plasma was 98.7%. This was achieved following a simple sample pretreatment method, prior to LCEC, involving chelation of divalent cations with EDTA and subsequent acidification with orthophosphoric acid, using the LCEC method. The circulating level of GSH in plasma, found in three normal subjects, was 14-15 μmol/liter, which is in agreement with previously reported values.