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The difficulty of deploying remaining oil from unconventional reservoirs and the increasing CO2 emissions has prompted researchers to delve into carbon emissions through Carbon Capture, Utilization, and Storage (CCUS) technologies. Under the confinement of nanopore in unconventional formation, CO2 and hydrocarbon molecules show different density distribution from in the bulk phase, which leads to a unique phase state and interface behavior that affects fluid migration. At the same time, mineral reactions, asphaltene deposition, and CO2 pressurization will cause the change of porous media geometry, which will affect the multiphase flow. This review highlights the physical and chemical effects of CO2 injection into unconventional reservoirs containing a large number of micro-nanopores. The interactions between CO2 and in situ fluids and the resulting unique fluid phase behavior, gas-liquid equilibrium calculation, CO2 adsorption/desorption, interfacial tension, and minimum miscible pressure (MMP) are reviewed. The pore structure changes and stress distribution caused by the interactions between CO2, in situ fluids, and rock surface are discussed. The experimental and theoretical approaches of these fluid-fluid and fluid-solid reactions are summarized. Besides, deficiencies in the application and safety assessment of CCUS in unconventional reservoirs are described, which will help improve the design and operation of CCUS.

Compared with the traditional fixed relay assisted communication network, the mobile relay assisted wireless communication network has greater communication coverage and better flexibility. It enables to extend the lifetime of a communication system and improve the throughput of uses. Due to the time-varying nature of the actual communication environment and the existence of various interferences, there are uncertain factors in the communication channel that affect the quality of service of users. In this paper, we study the energy efficiency maximization problem based on power control, mobile relay selection, and subcarrier allocation under uncertain channel. The proposed mobile relay selection and subcarrier allocation algorithm improves the energy efficiency of the system while ensuring the normal communication of mobile users. Probabilistic constraints are introduced into the optimization problem to describe the uncertain channel, and after the mathematical transformation, it becomes a solvable form. The subcarrier allocation algorithm and distributed robust power control algorithm are also presented. Simulation results show that the improved system energy efficiency has been achieved and the proposed algorithm behaves better scalability and robustness under dynamic communication environment.

In order to better meet the energy demand of rapidly developing electronic devices, it is urgent to develop electrode materials with high capacity and stability. In this article, we report a polyhedral carbon framework, which can evolve from a solid to hollow structure through rational design. Thanks to a good hollow, porous and thin shell structure, the material can be used for lithium–sulfur batteries (LSBs) and lithium/sodium ion batteries. For the lithium/sodium storage process, the capacity can be stabilized at 333.3 mA h g−1 (1000)/150.4 mA h g−1 (2000), even at a high current density of 10.0 A g−1. In addition, this unique material can also be used to modify commercial PP separators, which provides huge benefits to LSBs. The synergistic adsorption of polysulfides is achieved through physical/chemical interactions. It can provide a 625.4 mA h g−1 reversible capacity after 1000 cycles at a current density of 1.0C, and the capacity decay rate is as low as 0.046%. At the same time, this excellent cycle stability can be maintained under extremely high sulfur loading conditions. The sharing of this work emphasizes the importance of rational design of nanostructures for improving the cycle performance of secondary batteries.

Epidemiological data on cerebral venous thrombosis in China are still lacking at present on the aspects of incidence, recurrence, risk factors, and so on. Herein, we aimed to fill the gap, based on the result of this multicenter prospective cohort study. A total of 26 top tertiary hospitals distributed in China Mainland will take part in this study. For the first time, a dataset of cerebral venous thrombosis cohort (including multiethnic patients of all ages in almost all regions of Mainland China, regardless of gender) will be built. Inclusion criteria were as follows: (1) aged ≥14 years, (2) neuroimaging-confirmed cerebral venous thrombosis, (3) symptom onset was within 30 days prior to enrollment, (4) signed the informed consent form. Demographic data, risk factors, clinical and neuroimaging features, ophthalmologic and aural results, blood tests, cerebrospinal fluid examination, therapeutic strategies, and adverse events were analyzed. Two milliliters of fasting venous blood and 2 mL of cerebrospinal fluid will be collected and stored. Furthermore, patients will be followed up at months 1, 3, 6, and 12 after baseline assessment. Primary outcome will be all-cause mortality. Secondary outcomes: (1) cerebrospinal fluid pressure and Frisen grade; (2) recanalization rate on imaging; (3) rating scales such as GCS, NIHSS, mRS, Mini-Mental State Examination, Montreal Cognitive Assessment, Patient Health Questionnaire 9-item, HIT-6, and Tinnitus Handicap Index. This study will for the first time provide strong evidence on the incidence rate, recurrence rate, and demographic data, as well as special risk factors, clinical outcomes, symptomatic and imaging features of cerebral venous thrombosis in Chinese population. The results of this study will also provide an important reference on prevention, early diagnosis, and customized treatment of cerebral venous thrombosis in Chinese patients.

Lithium-sulfur (Li-S) batteries have fascinated as next-generation high specific energy density storing devices. Herein, we report the fabrication of a three-dimensional porous hollow core@shell st...

Thermal management of Al composites is a crucial issue to keep the promising performance and excellent reliability of the devices. We revealed a novel method to enhance the surface property of graphite flakes (GF) with Cu and Ni coatings by chemical plating way. Taking advantage of Cu and Ni co-doped GF and silicon powders, the GF@Cu@Ni/Si/Al composites were fabricated by vacuum pressure infiltration method. The GF@Cu-30@Ni-10 composites revealed about 2 times larger TC (474.4 W/m·K) and lower CTE 6.22 ppm/K than neat Al. Our strategy for highly TC offers not only the advanced process for dispersing reinforcements but also an extremely simple way for the anisotropic composites with high TC and low CTE.

In this report, hierarchically structured CoS2 was formed with ZIF-67 as a template. CoS2 nanoparticles are prepared through two processes, including carbonization and sulfurization. At the same ti...

Lithium–sulfur (Li–S) batteries with their low cost, high energy density, and theoretical specific capacity have been deemed as one of the most promising candidates for the future energy storage ma...

Three-dimensional (3D) flower-like Bi2SiO5 nanomaterials (FLB) and 3D flower-like Bi2SiO5@nitrogen doped graphene nanomaterials (FLBNG) have been originally synthesized. Notably, as-synthesized FLB and FLBNG nanomaterials have not yet been discussed in previous reports. The FLBNG nanomaterials have been for the first time studied as the cathodic catalysts for Fuel cell. Research results have shown that the FLBNG-2 possesses perfectly 3D flower-like Bi2SiO5 with numerous uniformly coiled nanowires and exhibits good methanol immunity, high activity and high durability during oxygen reduction reaction (ORR) process under acidic and basic electrolytes. The value of onset potential (E0) for FLBNG-2 in alkaline electrolyte can reach to 1.091 V, Tafel slope of FLBNG-2 is 45.637 mV dec−1 and its limiting current density (JL) is 6.49 mA cm−2. Similarly, These ORR performances in acidic electrolyte are also better than those of 20 wt% commercial Pt/C and most of the associated reports. Thus, the FLBNG-2 could be a potential ORR catalyst, applied in the cathode of fuel cells to enhance the kinetic rate, decrease costs and enhance durability. And this synthesis method may be provide a good design to synthesize other 3D flower-like nanomaterials with desirable properties.

Reasonable design of multi-component metal oxides hierarchical nanostructures is an effective and promising way to improve electrochemical performances of electrode materials. In this work, novel hydrangea-like ZnCo2O4/Ni3V2O8 hierarchical nanostructures are constructed by adjusting the ratio of ZnCo2O4 and Ni3V2O8. The perfect architecture maximizes the synergistic effect between different components and provides abundant electrochemical reactive sites, promoting the diffusion and transfer of electrolyte ions in electrochemical reaction process. As a result, ZnCo2O4/Ni3V2O8 electrodes deliver an enhanced specific capacitance of 1734 F g−1 at 1 A g−1 and cyclic stability (96% of initial capacitance is retained after 8000 cycles). Furthermore, the assembled ZnCo2O4/Ni3V2O8//AC device e achieves excellent energy density of 90 Wh kg−1 at power density of 812 W kg−1, proving the optimized hydrangea-like ZnCo2O4/Ni3V2O8 hierarchical nanostructures are promising electrode material for supercapacitor. In addition, this work supplies helpful insights into rational design of structure and composition of multi-component metal oxides for enhanced electrochemical performance.

Reasonable design for structure and composition of multi-component metal oxides is an effective and promising way to improve electrochemical performance of electrode materials. In this work, novel carnations-like Mn3O4@NiCo2O4@NiO hierarchical nanostructures are constructed by introducing CATB as structure-directing agents and adjusting hydrothermal reaction time. The perfect architecture maximizes the synergistic effect between components, providing more electrochemical reactive sites and promoting the diffusion and transfer of electrolyte ions. As a result, Mn3O4@NiCo2O4@NiO electrodes deliver an enhanced specific capacitance of 1905 F g−1 at 1 A g−1 and outstanding cyclic stability (92% of its initial capacitance is retained after 10000 cycles). Furthermore, ASC device which is assembled by the Mn3O4@NiCo2O4@NiO and activated carbon achieve excellent energy densities of 76.8 W h kg−1 at power densities of 800 W kg−1, proving the optimized Mn3O4@NiCo2O4@NiO is promising electrode material for supercapacitor. In addition, this work supplies helpful insights into rational design for structure and composition of multi-component metal oxides for enhancing electrochemical performance.

The hierarchical hollow framework involving interconnected highly conductive N-doped carbon nanotube networks and CoS2 particles were successfully prepared by metal-organic framework (MOF) derived method. After the two pyrolysis process in the atmosphere of reducing gas and inert gases, numerous carbon nanotubes interlaced on the surface of framework and CoS2 nanoparticles also attached on the surface. The electromagnetic parameters of CoS2/NCNTs composites can be well controlled by regulating the loadings of sample in sample-paraffin mixture. The results demonstrate that CoS2/NCNTs with 50% loadings show superior electromagnetic wave absorption properties in the wide frequency range, almost covering the whole X bands (8–12 GHz) only with a relative thin thickness of 1.6 mm. Hierarchical hollow structure and better impedance matching performance between N-doped carbon nanocube and CoS2 nanoparticles contribute to the enhancement of microwave absorption ability. Our work confirms that hollow framework CoS2/NCNTs composites can provide a novel idea for designing high-absorbability microwave absorbers.

Novel microporous carbon materials (DCMC) with excellent electron conductivity and ultrahigh surface area (1896.9 m 2 g −1 ) are successfully prepared from discarded clothes. The porous carbon-encapsulated sulfur composites were synthesized by a feasible melting process and used as host materials for lithium sulfur batteries. Because of the unique microporous, ultrahigh surface area and irregular wrinkled surface coexisting structure, the resulting microporous carbon/sulfur (DCMC/S) composite cathode possesses a good rate capability and long-term cycling performance. The initial discharge capacity of the DCMC2/S composite electrode with 74.3 wt% sulfur content is 1082.6 mAh g −1 at a current rate of 0.2 C. At a higher current rate of 1 C, it possesses excellent cyclic performance and retained a capacity of 422.8 mAh g −1 after 500 cycles with a low capacity fading rate of 0.11% per cycle. The coulombic efficiency remains over 98% during cycling.

Rational construction of unique hierarchical nanostructured electrodes with excellent electrochemical performance is a promising solution to satisfy the increasing demand of supercapacitors with high energy density. In this work, a novel nanostructure of bowl-like MnO2 nanosheets with ultra-thin thickness (about 4 nm) has been successfully designed by a simple template-assisted hydrothermal method. The composition and morphology of the obtained bowl-like nanostructures have been characterized by FESEM, TEM, XRD, XPS and N2 adsorption-desorption. Such novel nanostructures present several advantages, such as large surface area, compact contacts, reduced interior space, additional electroactive sites for reversible redox reactions and short/unimpeded diffusion channels for ions/electron transport. When evaluated as electrode materials, bowl-like MnO2 nanosheets exhibit a specific capacitance of 379 F g−1 at a current density of 0.5 A g−1, a capacitance retained ratio of 60.5% from 0.5 to 10 A g−1 and 87.3% capacitance retention after 5000 cycles. Moreover, a possible mechanism for the excellent electrochemical performance of the novel bowl-like nanostructures compared with hollow particles has been systematically studied. We believe that this strategy can open up an avenue and appropriate idea for the rational construction of other transition metal oxides with high performance for the practical supercapacitor applications.

Great efforts have been made on the assessment of the effects of nitrogen (N) fertilization or silicon (Si) addition on plant growth and community composition. However, their interactive effects were not well documented. We here tested the effects of N addition (0, 70, 140 and 210 kg ha−1 of N) on the leaf N content, growth, photosynthetic characteristics of five common species and structure of community (biomass, height, abundance and species richness) with or without Si (14.36 kg ha−1) incorporation. Different species and whole community responded different. As compared to without Si, Si incorporation increased the net photosynthetic rate (Pn) and biomass of species Elymus nutans by 16.7 and 31.1%, Kobresia capillifolia by 10.4 and 11.1%, Oxytropis kansuensis by 42 and 18.0%, Anemone rivularis by 14.3 and 157%, Potentilla fragarioides by 12.5 and 91.7%, plant abundance and species richness of community by 6.2 and 11.8% under N addition of 210 kg ha−1. The effect of Si supply on species richness was more efficient under low N addition than high N addition. Together, our results indicate that N fertilization incorporation with Si addition benefits plant growth for higher-photosynthetic activity of individual species and higher-species richness of community in alpine meadow.

Background Patients with early-stage renal cell carcinoma (RCC) are considered to be eligible donors. Although preliminary experience in using kidneys of specific pathologic types, mainly those with small renal masses (SRMs), have been established, multiorgan utilization of the same donor with SRMs is limited. Methods One deceased donor whose left-side kidney was diagnosed with Fuhrman grade I RCC was included. The tumor mass in the kidney was removed through partial nephrectomy according to the gold standard. Then, 3 transplant surgeries were performed, in which 1 recipient accepted kidney transplant after tumor exeresis, 1 simultaneous heart-kidney (the contralateral one) transplant, and 1 liver transplant. Recipients were followed up according to our standard protocol for renal cancers. (All allografts were allocated in compliance with the Declaration of Helsinki and the Declaration of Istanbul.) Results After 32 months, no radiographic findings showed any morphologic changes of the lesion, and all patients were in good condition, with neither tumor recurrence nor allograft rejection or infection. No complaints such as pain, oliguria, dyspnea, nausea, or fatigue were recorded. Conclusions To the best of knowledge, this initial work takes the lead in elaborating the organ utilization of multiorgan donors with SRMs. We hope the experience will provide support for cross discussion concerned with multiorgan transplant from tumor-affected donors in clinical practices, further expand the donor pool and address the donor shortage problem.

Purpose：To investigate the risk factors for calf venous thrombosis in patients with cerebral hemorrhage, so as to provide a reference for customized clinical decision.Methods：396 intracerebral hemorrhage (ICH) patients were enrolled in this retrospective study from January 2017 to December 2019. Risk factors and predictors of occurrence for Muscle calf venous thrombosis (MCVT) were summarized and analyzed by Chi-square test and logistic regression analysis.Results: 128 ICH patients with MCVT and 268 without ones were included. Demographic features comparison showed that ICH with MCVT patients showed older average age than those without ones (p=0.039). Co-morbid diseases analysis showed that patients with MCVT tend to complicate with Diabetes Mellitus (DM) (p=0.040). The comparison of laboratory examinations showed serum level of glucose (p=0.011), Fibrinogen (p=0.046) and D-Dimer (p=0.007) was significantly different. For clinical manifestations, the coma degree (GCS score) and muscle strength level were related to occurring of MCVT. Multivariate logistic regression identified higher age (OR=1.036, 95%CI =1.009-1.064, P= 0.008), higher D-Dimer level (OR=2.379, 95%CI =1.338-4.231, P= 0.003), low GCS (OR=0.932, 95%CI =0.868-0.998, P= 0.044) and lower affected side muscle strength (0-3 grade) (OR=1.624, 95%CI =1.009-2.614, P= 0.046) will predict higher incidence of MCVT in ICH patients.Conclusion: According to our study, higher age, higher D-Dimer level, lower GCS score and lower affected side muscle strength were associated with higher incidence of MCVT in ICH patients. Clinical doctors should pay more attention to prevent MCVT in ICH patients which coincide with those risk factors.

A simple synthesize method of hybrid transition metal oxides is important for the application of electrodes materials. In this work, we report one-pot hydrothermal method to synthesize 3D hierarchical MnMoO4/NiWO4 microspheres. Notably, the 3D hierarchical MnMoO4/NiWO4 microspheres electrodes with a MnMoO4/NiWO4 molar ratio of 4:3 present outstanding electrochemical performance. The excellent specific capacitance of the hybrid materials is 598 F g-1 at a discharge current density of 1 A g−1 and the capacitance retains 82% of its initial capacitance even after 5000 cycles, which are attributed to the obtained 3D hierarchical MnMoO4/NiWO4 microspheres are constituted by self-assembly MnMoO4 nanoflakes and NiWO4 nanoparticals and feature with abundant transportation shortcuts for electrolyte ions and excellent electrochemical performance. The results reveal that the 3D hierarchical MnMoO4/NiWO4 microspheres have great application prospect for electrochemical energy storage and the quick and facile method provides a new avenue for the preparation of hybrid materials.

Integrating polyaniline (PANI) with different dimensional carbon materials is considered as a promising strategy to solve the disadvantages of PANI electrodes, such as low rate capability and poor cyclic stability. In this work, a novel layer-by-layer sandwiched graphene/PANI nanorods/carbon nanotubes (G/PANI/CNTs) heterostructure has been synthesized. The morphology of the heterostructures has been characterized by XRD, Raman spectroscopy, N2 adsorption-desorption, XPS, FESEM and TEM. The obtained new layer-by-layer sandwiched heterostructures exhibit intimate interface contacts, fully network-structured CNTs coating, dual physical supports and synergistic effects, which can effective host the electrochemical properties of PANI with the electrolyte and restrain the volumetric changes of PANI. As a result, the electrodes exhibit high specific capacitance (638 F g-1 at 0.5 A g−1), good rate capability (88.2% retention from 0.5 A g−1 to 10 A g−1) and long cycle stability (93% of the initial specific capacitance after 2000 cycles) when the amount of CNTs is 2 mg. Moreover, a possible mechanism for good performance of the layer-by-layer sandwiched heterostructures has been systematically studied. We believe that this strategy will open up an avenue for the rational design of sandwich structured electrodes for high performance supercapacitors and other electronic devices.

The classical Back-Propagation (BP) scheme with gradient-based optimization in training Artificial Neural Networks (ANNs) suffers from many drawbacks, such as the premature convergence, and the tendency of being trapped in local optimums. Therefore, as an alternative for the BP and gradient-based optimization schemes, various Evolutionary Algorithms (EAs), i.e., Particle Swarm Optimization (PSO), Genetic Algorithm (GA), Simulated Annealing (SA), and Differential Evolution (DE), have gained popularity in the field of ANN weight training. This study applied a new efficient and effective Shuffled Complex Evolutionary Global Optimization Algorithm with Principal Component Analysis – University of California Irvine (SP-UCI) to the weight training process of a three-layer feed-forward ANN. A large-scale numerical comparison is conducted among the SP-UCI-, PSO-, GA-, SA-, and DE-based ANNs on 17 benchmark, complex, and real-world datasets. Results show that SP-UCI-based ANN outperforms other EA-based ANNs in the context of convergence and generalization. Results suggest that the SP-UCI algorithm possesses good potential in support of the weight training of ANN in real-word problems. In addition, the suitability of different kinds of EAs on training ANN is discussed. The large-scale comparison experiments conducted in this paper are fundamental references for selecting proper ANN weight training algorithms in practice.

The realization of the high energy density of lithium-sulfur batteries (Li-S) has always been one of the targets pursued by researchers. However, the shuttling effect, dissolution of sulfur/lithium polysulfides (LiPSs), and sluggish redox kinetics in Li-S batteries restricted its long-term application and development. Herein, an advanced sulfur immobilizer composed of SnP0.94 nanodot electrocatalysts@porous hollow carbon aerogel (SnP0.94@PHCA) was synthesized. As expected, the synergistic sulfur host can not only act as a good electrochemical interface but also provide adequate accommodation for active materials to alleviate the LiPS diffusion. More importantly, SnP0.94 nanodot electrocatalysts supported on the conductive PHCA skeleton effectively expedited the conversion/redox reaction kinetics and also constructed a stronger adsorption system for LiPSs to inhibit the LiPS shuttling behavior. Correspondingly, the SnP0.94@PHCA composite endowed the sulfur cathode the outstanding specific capacity of 1017.8 mAh g−1 under a high sulfur loading (2.94 mg cm−2) at 0. 1 C, superior rate performance (579.8 mAh g−1 at 1 C), excellent cycling stability (the capacity decay rate of 0.13% per cycle at 0.5 C), and a high areal capacity of 6.9 mAh cm−2 under starved electrolyte conditions (8.6 μL mgs−1). This work opens up a new direction for constructing the electroactive hosts in Li-S batteries.

In the development of a satellite-based precipitation product, two important aspects are sufficient precipitation information in the satellite-input data and proper methodologies, which are used to extract such information and connect it to precipitation estimates. In this study, the effectiveness of the state-of-the-art deep learning (DL) approaches to extract useful features from bispectral satellite information, infrared (IR), and water vapor (WV) channels, and to produce rain/no-rain (R/NR) detection is explored. To verify the methodologies, two models are designed and evaluated: the first model, referred to as the DL-IR only method, applies deep learning approaches to the IR data only; the second model, referred to as the DL-IR+WV method, incorporates WV data to further improve the precipitation identification performance. The radar stage IV data are the reference data used as ground observation. The operational product, Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks–Cloud Classification System (PERSIANN-CCS), serves as a baseline model with which to compare the performances. The experiments show significant improvement for both models in R/NR detection. The overall performance gains in the critical success index (CSI) are 21.60% and 43.66% over the verification periods for the DL-IR only model and the DL-IR+WV model compared to PERSIANN-CCS, respectively. In particular, the performance gains in CSI are as high as 46.51% and 94.57% for the models for the winter season. Moreover, specific case studies show that the deep learning techniques and the WV channel information effectively help recover a large number of missing precipitation pixels under warm clouds while reducing false alarms under cold clouds.

The effect of RE2O3 (RE = La, Ce) fluxes on penetration and microstructure in 3-mm-thick Ti6Al4V weld joints made by activated flux tungsten inert gas (A-TIG) welding process was investigated. The mechanism of penetration increase was discussed. Microstructure characterization in the fusion zone region was also observed under optical microscope. It is shown that RE2O3 fluxes can effectively increase weld penetration of Ti6Al4V for applying a thin layer paste when welding. The mechanism would comply with changing the Marangoni convection in the weld pool, rather than the arc. A-TIG welding with RE2O3 fluxes can slightly refine the width of β-Ti grains. Phase constitution shows single α′-Ti in solidification structure in both two welding process. There are no significant changes in weld metal microstructure with and without Re2O3 fluxes. Microhardness distribution of weld seam indicates that the appearance of RE2O3 has not affected the metal plastic deformation capacity.