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To solve influence of the uncertainty in integrated energy system on dispatch plan, a interval multi-objective optimization dispatch method of integrated energy system under multiple uncertain factors is proposed. Firstly, interval mathematics is used to describe multiple uncertain factors in the system, such as efficiency of multi-energy coupling unit, demand response, and electricity substitution; secondly, considering the efficient use of energy, the economics of system operation and difference in energy quality, optimize the operation of the system with goal of lowest system operating cost and highest exergy efficiency; finally, based on interval multi-objective linear programming method, an interval multi-objective optimization scheduling technique of integrated energy system under multiple uncertain factors is established. Case analysis shows that proposed multi-objective optimization scheduling method can take economics of system operation and exergy efficiency into account, and effectively improve the system's ability to deal with multiple uncertainties. more...

ObjectiveTo investigate the safety and efficacy of selective intraarterial hypothermia combined with mechanical thrombectomy in the treatment of acute cerebral infarction based on microcatheter technology.MethodsA total of 142 patients with anterior circulation large vessel occlusion were randomly assigned to the hypothermic treatment group (test group) and the conventional treatment group (control group). National Institutes of Health Stroke Scale (NIHSS) scores, postoperative infarct volume, the 90-day good prognosis rate (modified Rankin Scale (mRS) score ≤ 2 points), and the mortality rate of the two groups were compared and analyzed. Blood specimens were collected from patients before and after treatment. Serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-6 (IL-6), IL-10, and RNA-binding motif protein 3 (RBM3) were measured.ResultsThe 7-day postoperative cerebral infarct volume [(63.7 ± 22.1) ml vs. (88.5 ± 20.8) ml] and NIHSS scores at postoperative Days 1, 7, and 14 [(6.8 ± 3.8) points vs. (8.2 ± 3.5) points; (2.6 ± 1.6) points vs. (4.0 ± 1.8) points; (2.0 ± 1.2) points vs. (3.5 ± 2.1) points] in the test group were significantly lower than those in the control group. The good prognosis rate at 90 days postoperatively (54.9 vs. 35.2%, P = 0.018) was significantly higher in the test group than in the control group. The 90-day mortality rate was not statistically significant (7.0 vs. 8.5%, P = 0.754). Immediately after surgery and 1 day after surgery, SOD, IL-10, and RBM3 levels in the test group were relatively higher than those in the control group, and the differences were statistically significant. Immediately after surgery and 1 day after surgery, MDA and IL-6 levels in the test group were relatively reduced compared with those in the control group, and the differences were statistically significant (P < 0.05). In the test group, RBM3 was positively correlated with SOD and IL-10.ConclusionMechanical thrombectomy combined with intraarterial cold saline perfusion is a safe and effective measure for the treatment of acute cerebral infarction. Postoperative NIHSS scores and infarct volumes were significantly improved with this strategy compared with simple mechanical thrombectomy, and the 90-day good prognosis rate was improved. The mechanism by which this treatment exerts its cerebral protective effect may be by inhibiting the transformation of the ischaemic penumbra of the infarct core area, scavenging some oxygen free radicals, reducing inflammatory injury to cells after acute infarction and ischaemia–reperfusion, and promoting RBM3 production in cells. more...

Since initiating reform and opening up, especially since acceding to the World Trade Organization in 2001, China has made remarkable progress in international trade and economic development. Under ... more...

The bismuth oxide (Bi

The disproportionation of alcohols without an additional reductant and oxidant to simultaneously form alkanes and aldehydes/ketones represents an atom-economical transformation. However, only limited methodologies have been reported, and they suffer from a narrow substrate scope or harsh reaction conditions. Herein, we report that alcohol disproportionation can proceed with high efficiency catalyzed by iodide under acidic conditions. This method exhibits high functional group tolerance including aryl alcohol derivatives with both electron-withdrawing and electron-donating groups, furan ring alcohol derivatives, allyl alcohol derivatives, and dihydric alcohols. Under the optimized reaction conditions, a 49% yield of 5-methyl furfural and a 49% yield of 2,5-diformylfuran were obtained simultaneously from 5-hydroxymethylfurfural. An initial mechanistic study suggested that the hydrogen transfer during this redox disproportionation occurred through the inter-transformation of HI and I2. Radical intermediates were involved during this reaction. more...

With the popularization of intravenous thrombolysis, more and more people use intravenous thrombolysis to treat related diseases, but problems also arise. There are still a considerable number of patients with early disease after thrombolytic therapy not only not significantly improving, but also progressing, that is, early neurological deterioration (END). In view of this problem, the prediction of END after intravenous thrombolysis becomes very important. With the development of medical technology, research on the prediction of END after intravenous thrombolysis has gradually been carried out. Effective prediction is of great significance for the prevention and treatment of END after intravenous thrombolysis. This article aimed to carry out a meta-analysis of the predictive role of END after intravenous thrombolysis. Through an informed analysis of all studies of this type in this field, this article determines a method for predicting END after intravenous thrombolysis. The actual effect of its role is revealed in this paper, and its purpose is to promote the development of this field. This article addresses the same type of study on the predictive role of neurological deterioration after intravenous thrombolysis. The article performs test and meta-analysis of its role by conditionally searching for literature studies. It is explained using the relevant theoretical formulas. The analysis results show that the prediction of END after intravenous thrombolysis in this paper can effectively help make a preliminary judgment on the possible later neurological deterioration. Although there is an error between the predicted curve and the actual curve, the difference between the two is between 1% and 5%. It can basically effectively predict the occurrence of END. Therefore, the prediction of END after intravenous thrombolysis has a very large preventive effect on the END after intravenous thrombolysis. more...

The wide-spectrum integrated imaging method can simultaneously obtain the spectral information of different spectral bands of the same target, which is conducive to the realization of the high-precision detection of target characteristics, and can simultaneously obtain more comprehensive elements such as the structure, shape, and microphysical parameters of the cloud. However, for stray light, the same surface has different characteristics at different wavelengths, and a wider spectral band means more complex and diverse sources of stray light, which renders the analysis and suppression of stray light more difficult. In this work, according to the characteristics of the visible-to-terahertz integrated optical system design scheme, the influence of material surface treatment on stray light was studied; the stray light analysis and optimization of the whole link of light transmission were carried out. For the sources of stray light in different channels, targeted suppression measures such as front baffle, field stop, special structure baffle, and reflective inner baffle were adopted. The simulation results indicate that when the off-axis field of view was greater than 10°. The point source transmittance (PST) of the terahertz channel is on the order of 10−4, the visible and infrared channels are less than 10−5, and the final terahertz PST was on the order of 10−8, while visible and infrared channels were lower than 10−11. Here, we present a method for stray light suppression based on conventional surface treatments for broadband imaging systems. more...

Using data of China’s listed companies from 2000 to 2016, we employ a staggered difference-in-difference (DID) approach to identify the causal effects of CEO turnover on corporate innovation. First, we find that listed companies with CEO turnover experienced an average increase of 9.5% in the quantity of innovation and 8.9% in innovation quality after the change. The dynamic effect test supports the parallel trend condition, and the placebo test rules out the nonrandom selection issue. Second, the heterogeneity tests show that CEO turnover plays a more prominent role in promoting innovation for listed firms with CEO duality, high financial constraints, and in high-tech industries. Third, CEO turnover affects corporate innovation by driving top management team reorganization and promoting R&D input. This paper has important implications for the understanding of the role of CEO turnover in companies’ innovation, as well as for strategy formulation and implementation. more...

The rapid expansion of rubber plantations in Xishuangbanna, China, has severely decreased rubber prices in the last several years. The income loss and other adverse environmental impacts have brought livelihood challenges and opportunities to develop and adopt more diversified and environmental-friendly income-generating activities (IGAs). To better understand the constraints and opportunities for smallholder rubber farmers to sustain or improve their livelihoods, this study investigates which IGAs are applied by local farmers and the factors that determine their adoption, using the sustainable livelihood framework as the theoretical guideline. The qualitative approach is applied using semi-structured interviews and thematic analysis. Five directions of changes in IGAs (i.e., intercropping, other cash crops, livestock raising for marketing, part-time job, and land renting) are identified, and local farmers are categorized into three groups (i.e., rejective, affirmative, and hesitate groups) based on their attitudes towards these IGAs. The results reveal that the main adoption motivations of certain IGAs are closely related to price shock, economic return, information, and extension service. Based on the results, suggestions are provided to enhance farmers’ motivation to make changes and improve the adoption of emerging IGAs with attention given to vulnerability contexts, livelihood assets and institutional assistance. more...

This study presents a new approach to the optimal placement of voltage sag monitors considering the uncertainties associated with transition resistance. The influence of transition resistance on the magnitude of voltage sags triggered by symmetrical and unsymmetrical faults is analyzed. Then the transition resistance interval set array for voltage sags is established, on the basis of which, a random vector model on voltage sag observability is proposed and related observability indices are defined in the form of conditional probability. The optimal placement model is established by taking the available number of monitors as the constraint condition and the maximum sag global observability index as the objective function. Binary particle swarm optimization (BPSO) is implemented to obtain the optimal placement results. Finally, simulation is carried out on IEEE 30-bus system, and it is shown that the proposed optimal monitor placement method is more applicable compared with the traditional MRA method. more...

For the increasing well plugging in oilfield development, a new unplugging technology is presented in this paper for the downhole plugging by using high voltage pulse wave. Based on the mechanism analysis, the circuit resistance model and the empirical calculation formula of the pressure shock wave are obtained, and the influence of the same current waveform on the pressure shock wave generated by the wire explosion is preliminarily studied in laboratory experiments under different energy conditions. A corresponding unplugging evaluation test device was designed to simulate the approximate downhole reservoir conditions in the places where the shock wave occurs to test the approximate downhole stress conditions of the core, and to test the permeability changes after different shock waves acted on the core. The results show that the peak value of the pressure shock wave is proportional to the effect of well unplugging, which verifies the feasibility of the unplugging and increasing permeability technology of the electric explosion-controlled shock wave. This technology can quickly dredge the oil seepage channel, increase well permeability, thus increasing the well productivity, which has a broad application prospect and important practical significance. more...

The hydrothermal liquefaction (HTL) of As enriched Pteris vittata L. (PVL, hyper-accumulator biomass) was performed with the recycled aqueous phase as reaction medium, aiming to dispose the biomass with high water content and produce high-quality bio-oil. After three times of aqueous phase recycling at 275 °C, 30 min, the bio-oil yield increased to 30.32% from 21.54% and the higher heating value (HHV, 28.51 MJ/kg) of the bio-oil was higher than that of the bio-oil from HTL with pure water (26.80 MJ/kg). The main compounds detected in bio-oils were phenols, ketones, hydrocarbons, and aldehydes. Acetic acid (17.21–24.77 mg/mL) was dominant in the aqueous phases, resulting in the low pH (4.31–4.89). The heavy metals (Cu, Pb, Zn, Cd) mainly remained in bio-char whereas As was transferred to aqueous phase. Thus, HTL by aqueous phase recycling could be a promising way for PVL treatment to obtain high-quality bio-oil and arsenic recovery. more...

Cesium tungsten bronze (Cs0.33WO3) coatings can effectively depress solar heat gain and air-conditioning energy consumption of buildings, because of their highly selective near infrared (NIR) absorbing ability. However, the absorbed solar energy may overheat the window glasses due to the high photothermal conversion efficiency of Cs0.33WO3 coatings, discounting their transparent heat insulating performance. To solve this issue, we design a new energy-efficient composite window by integrating NIR-shielding Cs0.33WO3 with phase change materials (PCMs, paraffin wax in our case). In the composite window, the hexagonal-phase Cs0.33WO3 is prepared by a solid-state reaction method, and then coated onto commercial float glass as Cs0.33WO3–SiO2 composite films via a sol–gel process. Afterwards, a homemade double-plane window consisting of a float glass and a Cs0.33WO3–SiO2-coated glass is filled by molten commercial paraffin wax to obtain the paraffin wax–Cs0.33WO3 composite window. Cs0.33WO3 in the window can reduce solar heat gain of the buildings. Meanwhile, the paraffin wax component can accumulate the Cs0.33WO3-captured thermal energy by its endothermic molting processes, protecting the window from overheating. When the ambient temperature drops low enough, the stored thermal energy in the paraffin wax can be gradually released back by reverse solidifying processes. Therefore, this paraffin wax–Cs0.33WO3 composite window should be very effective to keep indoor temperature stable and comfortable. Performed on a homemade house model, the paraffin wax–Cs0.33WO3 composite window can depress indoor temperature variation from 24.2 down to 7.3 °C, compared with a bare glass window. This composite window is expected to improve energy efficiency of buildings locating in areas with high day–night or summer–winter temperature fluctuations. more...

As-enriched Pteris vittata L. (PVL, a kind of hyper-accumulator biomass) was converted into high-quality biofuel by the catalytic hydrogenolysis, aiming to achieve effective treatment and high-value utilization of hyper-accumulators. After pretreatment of PVL to remove lipids and lignin, more than 64% of heavy metals were transferred into water, and the As content in the solid biomass was reduced from 1328 mg/kg to 483 mg/kg. The multifunctional catalysts RhCl3/NaI/HCl/H2 were used in a biphasic reaction system to convert PVL into biofuel with high selectivity. The main products are C5 and C6 furans and low oxygen content ketones, which have a high heating value (HHV) and can be directly used as biofuel. The highest yields of C5 and C6 products were obtained with 60.2% and 61.1% (based on the corresponding hemicellulose and cellulose) under the optimal reaction conditions (160 °C, 4 h, 300 psi H2, 4 mmol NaI, H2O/toluene = 1:1). The total biofuel yield based on dry PVL was 18.8 wt.%. After the reaction, more than 50% heavy metals (Cu, Pb, Zn, Cd, As) remained in the bio-char, while the heavy metals in the biofuel were less than 20% (As content was less than 55 mg/kg). Therefore, catalytic hydrogenolysis was perceived as a promising technique for PVL treatment to obtain high-quality biofuel and arsenic recovery. more...

The high nitrogen content in bio-oil from protein-rich biomass will cause the possible pollution problems by NOX emissions during combustion. In this study, Cd-enriched Amaranthus hypochondriacus L. (AHL) was treated by hydrothermal liquefaction (HTL) in ethanol–water co-solvent aiming to reduce the nitrogen content of the bio-oil. Besides, aqueous phase recycling (APR) was applied to achieve a higher bio-oil yield. HTL in ethanol–water co-solvent with APR three times resulted in the maximum bio-oil yield (47.26%) and greatly reduced the nitrogenous compounds content of bio-oil. During the APR process, the increase of total nitrogen (TN) content in the aqueous phase indicated that organic-N in the organic phase transformed into NH4+ to the aqueous phase. Acetic acid (13.87–22.37 mg/mL) was dominated in the aqueous phase, leading to a low pH value (6.27–5.29), which could serve as the possible catalyst for the HTL process during APR that can be the reason for the higher bio-oil yield. After the HTL process, Cr, Cu, Cd and Pb remained mostly in bio-char while As was present largely in the aqueous phase. Thus, this study demonstrated that the APR for HTL process in ethanol–water co-solvent can be a hopeful method to dispose the high-protein biomass for improved bio-oil yield and quality. more...

A continuous-stirred microwave pyrolysis (CSMP) reactor was designed for linear low-density polyethylene (LLDPE) conversion. Its performance was compared with the batch microwave pyrolysis (BMP) under identical conditions. During the pyrolysis, the continuous-stirred system generated more condensate products with higher selectivity in long carbon chains (C14–C20), whereas the batch system was more selective for gas products with a higher proportion of methane. An ex-situ catalytic bed with HZSM-5 was assembled to upgrade pyrolysis vapors, corresponding to improved gasoline-range hydrocarbons and propylene production. The comparison of catalytic processes showed similar product yields for both configurations, with differences primarily on chemical species selectivity. For instance, the products from the continuous-stirred system had narrower carbon number distribution (C7–C10) and higher selectivity to mono-aromatics (72.3%). The proposed pathways for LLDPE conversion from the two systems showed slight differences in the thermal cracking process but similarities in the catalytic cracking process. During the catalytic processes, the potential net energy gain was 34.16 MJ/kg for CSMP and −38.86 MJ/kg for BMP, compared with the non-catalytic processes, when the figures were 9.85 MJ/kg and −42.86 MJ/kg, respectively. more...

A continuous-stirred microwave pyrolysis (CSMP) reactor coupled with an ex-situ catalytic bed was developed for the conversion of linear low-density polyethylene (LLDPE) to high-grade fuels. Effects of catalyst-to-reactant ratio and feeding rate on product yield and chemical selectivity were studied. The CSMP of LLDPE produced up to 84.1 wt.% condensate product composed of hydrocarbon fuels. With the assistance of the ex-situ catalytic process with HZSM-5, more refined chemicals dominated by gasoline-range hydrocarbons (C5–C12 hydrocarbons) were observed. When the catalyst-to-reactant ratio was 15 % and the feeding rate was 6 g/min, the condensate oil with a high higher heating value (45.23 MJ/kg) showed the highest selectivity of gasoline-range hydrocarbons (98.0 %). The pyrolysis processes yielded ethylene as the main gas product. With the addition of HZSM-5, propylene and propane were the primary gas components. The plausible pathway for the conversion of LLDPE mainly proceeded through radical mechanism for pyrolysis and carbenium ion mechanism for catalysis was elaborated. The potential net energy gain increased from 34.16 MJ/kg to 48.91 MJ/kg with growing feeding rate from 6 g/min to 30 g/min. more...

Both Mo and W belong to VIB-sub-group, and possess similar ionic radii, electronegativity and oxide lattice configuration. Herein, Mo-doped (0–80 at.%) tungsten bronzes, M x WO 3 , were hydrothermally prepared to systematically explore the influence of Mo-doping on their micro-structure and optical performance. The products adopted a hexagonal structure within 6 at.% Mo-doping, and transformed into a monoclinic phase with higher Mo-doping content. Further tests suggested that 1.5 at.% Mo-doping is beneficial for the formation of pure hexagonal phase and uniform nano-rod morphology. Optical measures showed that all samples exhibited high and comparable visible transmittance (70–80%), but a very different near infrared (NIR) shielding ability. The sample doped with 1.5 at.% Mo demonstrated the best NIR shielding ability with a transmittance minimum of 20% at 1300 nm. Further increase of Mo-doping dosage remarkably deteriorated NIR shielding ability by depressing the absorption of localized surface plasmon resonance (LSPR). However, the optical absorption from small-polaron was less influenced by the introduction of Mo. As a result, Mo-doping caused an evident blue shift of the infrared absorption peaks from 1350 to 750 nm. more...

Micro-porous activated carbons (ACs) with a narrow pore size distribution of 0.4–0.6[Formula: see text]nm and high specific surface areas (1160–1315[Formula: see text]m2[Formula: see text][Formula: see text] g[Formula: see text] are prepared from environment-friendly, low-grade potassium humate (HA-K, carbon resource) and mild activating agent potassium acetate (CH3COOK). Microstructure characterizations indicate that the introduction of activating agent CH3COOK is a key step to achieve high specific surface area and carbonization degree. These ACs contain small amount of oxygen and nitrogen, and show obvious pseudo-capacitance besides double layer capacitance. As a result, the optimized ACs achieve high specific capacitances of 311[Formula: see text]F[Formula: see text][Formula: see text][Formula: see text]g[Formula: see text] and 317[Formula: see text]F[Formula: see text][Formula: see text][Formula: see text]g[Formula: see text] at 0.1[Formula: see text]A[Formula: see text][Formula: see text][Formula: see text]g[Formula: see text] in 2[Formula: see text]M KOH and 1[Formula: see text]M H2SO4aqueous electrolytes, respectively. This sample also shows a good charge-discharge cycling stability within 10 000 cycles. more...