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With hydrophobic associating polymer (BCG-1) and anionic surfactant sodium dodecyl benzene sulfonate (SDBS) solution as the object, this work studies the different polymer concentration and surfactant concentration on the influence law of fluid properties and examines the sand sedimentation rate and the correlation of fluid properties. After the liquid was tested by electron microscope and rheometer, it was found that the interaction between the surfactant and the polymer is with phases, which provided different angles for revealing the change rule of the deposition rate of sand. When the concentration of SDBS solution is in the second phase (0.05–0.2%), although the system property changes slightly and the microscopic morphology does not change greatly, the deposition rate of sand still decreases significantly. Relaxation time spectrometry explains that the reduction in the sedimentation rate of the sand is caused by the shift of the polymer chain motion mode, whereas the phase angle can clearly manifest this change, and the phase angle is highly correlated with the deposition rate of sand.

A kind of JDL-1 thickener for betaine hydrophobic association polymer was prepared by aqueous solution polymerization of mixed micelles, AM, AA, AMPS and DM16 were used as raw materials, which was synthesized by redox initiator system. Friction tester and high-temperature rheometer were used to evaluate the resistance reduction and temperature and shear resistance of the thickener. The results show that the viscosity average molecular weight of the polymer prepared with AM, AA, AMPS and DM16 mass ratio of 70∶20∶5∶5 was higher than 12 million, and the dissolution time of the polymer was less than 3 min. When the surfactant is used for physical cross-linking, the apparent viscosity of the cross-linked fracturing fluid is larger than that of 60 mPa·s at 90 °C, 170 s-1 sheared 1 h; when metal cross-linking agent is used for coordination cross-linking, the apparent viscosity is larger than that of 80 mPa·s at 120 °C, 170 s-1 sheared 1 h. The drag reduction rate was 73%, the anti-swelling rate was higher than70%, and the damage rate was less than10%. The field trial was successful and confirmed the multifunctional effect of betaine-type hydrophobic associating polymer.

Wire supercapacitors have recently elicited attention due to their potential to be woven into textiles as flexible power supplies for wearable electronic devices. However, contemporary wire supercapacitors generally suffer from low energy density and complicated fabrication and assembly processes. Here, we report a unique design of asymmetric wire supercapacitors in a wrap-twist architecture, with graphene nanopetals grown on carbon fiber tow as negative electrodes and MnO2nanosheets electrodeposited on carbon nanotube paper as positive electrodes. The wrap-twist structure integrates both positive and negative electrodes with edge-enriched nanostructures, and a new assembly procedure greatly increases the contact area between the two electrodes, leading to significantly improved electrochemical performance. Such asymmetric wire supercapacitors exhibit ultrahigh capacitances of over 40 mF cm−1, outstanding energy and power densities, with energy densities up to 12 µWh cm−1(approx. 50 µWh cm−2on an area basis) and power densities up to approx. 3.7mWcm−1(approx. 15.4mWcm−2), good cyclic stability and excellent flexibility. Moreover, the thermal performance of such wire supercapacitors is assessed by characterizing temperature effects on electrochemical performance over a temperature window ranging from 2 to 80°C. The outstanding electrochemical and thermal performance of the wire supercapacitors demonstrates their promising potential as flexible power sources for wearable electronic devices.

Rock brittleness is an important parameter for evaluating the fracability of the unconventional oil and gas reservoirs such as tight sandstone and shale oil. Compared with the laboratory measurement, rock brittleness in 3D stratum using the joint inversion of seismic and well logs is more significant for oil exploration and development, but the resolution of the inversion results is low due to the narrowly effective bandwidth of seismic data. Deep neural network (DNN) can establish the complex nonlinear mapping relationship between input and output data to improve the resolution of inversion results, but it has the problem of unstable prediction results in the case of insufficient training samples in the geophysical field. Aiming at the problem, firstly, the ratio of Young ‘s modulus to Poisson ‘s ratio is defined as the rock brittleness index, and an AVO approximation equation with brittleness index is derived, thus establishing the convolution model between the rock brittleness index and seismic data. Secondly, an objective function containing the loss of logging data, seismic data and low-frequency components obtained by the inverse distance weighted interpolation of seismic and well logs is proposed to improve the spatial constraints of seismic and well logs. Then, the spatiotemporal attention mechanism is fused with the convolutional neural network (CNN) and gate recurrent unit (GRU) network to improve the sensitivity of the network proposed to important spatiotemporal characteristics. Finally, a DNN based on the double constraints of convolution model and data is established to solve the inversion stability in the case of small samples. The inversion results of the geological model with sand body superposition and pinchout and the tight sandstone reservoir in Junggar Basin verify that the generalization and prediction accuracy of the network proposed.

The molecular complexity and the low solubility of petroleum hydrocarbon residuals in weathered soil hinder bioremediation as a clean-up strategy. Pretreatment with advanced oxidation, such as with ozone gas (O3), is a means to transform recalcitrant organics to more biodegradable forms. The efficacy of gas-phase ozone for enhancing the biodegradability of heavy residual petroleum hydrocarbons in weathered soil was tested. Ozonating soil containing ∼1%  (w/w) residual petroleum hydrocarbons with a dose of 6  kg  ozone/kg initial total petroleum hydrocarbons (TPHs) achieved nearly 50% TPH reduction, simultaneous with a >20-fold increase in soluble chemical oxygen demand, but with a ≤12% loss of total organic carbon. TPH molecules were converted to partly oxidised products, ten of which were identified as n-monocarboxylic acids, which were readily biodegraded, and ozonation resulted in a fourfold increase in 5-d biochemical oxygen demand (BOD5). BOD5results after ozonation were the same with or without a microbial seed, which suggests that bioaugmentation is likely not necessary after ozonation. Deoxyribonucleic acid sequencing over the time course of the BOD5tests showed increased diversity and changes in predominant genera, both of which underscore that ozonation made the heavy hydrocarbons readily biodegradable for soil bacteria.

The coking kinetics and reaction-regeneration on Zn/HZSM-5 (Zn/HZ) catalyst in the conversion of methanol to aromatics were investigated. The highest initial benzene, toluene and xylene (BTX) yield of ca. 67.7% was obtained on fresh Zn/HZ catalyst, which showed the worst catalytic stability. The cycle of reaction-regeneration significantly modified the texture and acidity of Zn/HZ catalyst, which in turn affected its catalytic performance and coking behavior in methanol conversion to BTX. The residual carbon located on the surface of Zn/HZ catalyst led to the decrease of acid sites and the change on the acid sites distribution, which played an important roles on its activity and deactivation. It was found that the high B/L ratio and the low total acid sites concentration of the Zn/HZ catalyst favored to the high BTX yield and good catalytic stability in methanol conversion.

Influenza is a serious public health problem that endangers the health of the global human population. Traditional Chinese medicine (TCM) is rich in theory and practical experience regarding the treatment of influenza, and TCM treatments have shown good curative effects, but there is a dearth of standardized clinical guidance. It is necessary to formulate a clinical practice guide based on evidence-based medicine. To this end, the Specialty Committee of Emergency, China Association of Chinese Medicine (Beijing, China) organized a team of clinical experts, methodological experts, and other multidisciplinary experts to develop a guideline with integrated research methods in the first place of TCM. This guide includes 23 recommendations. The prescription section contains 16 recommendations, including 5 recommendations for mild cases, 5 recommendations for severe cases, 3 recommendations for critical cases, and 4 recommendations for the recovery period; the portion covering proprietary Chinese medicines forms a total of 7 recommendations. This guide aims to provide the best evidence for clinicians and related practitioners to make decisions about influenza diagnosis and treatment in Chinese medicine.

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