Synthesis of crystalline g-C_(3)N_(4) with rock/molten salts for efficient photocatalysis and piezocatalysis

Graphitic carbon nitride(g-C_(3)N_(4))is emerging as a promising visible-light photocatalyst while the low crystallinity with sluggish charge separation/migration dynamics significantly restricts its practical applications.Currently,synthesizing highly crystalline g-C_(3)N_(4) with sufficient surface activities still remains challenging.Herein,different from using alkali molten salts which is commonly reported,we propose an approach for synthesis of highly crystalline g-C_(3)N_(4) with FeCl3/KCl rock/molten mixed salts.The rock salt can serve as the structure-directing template while molten salt provides the required liquid medium for re-condensation.Intriguingly,the synthesized photocatalyst showed further enhanced crystallinity and improved surface area along with high p/p*excitation compared with crystalline C_(3)N_(4) prepared from conventional molten-salt methods.These catalytically advantageous features lead to its superior photocatalytic and piezocatalytic activities with a high reactivity for overall water splitting that is not commonly reported for C_(3)N_(4).This work provides an effective strategy for structural optimization of organic semiconductor based materials and may inspire new ideas for the design of advanced photocatalysts.

Constructing Crystalline g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x)Isotype Heterostructure for Efficient Photocatalytic and Piezocatalytic Performances

Graphitic carbon nitride(g-C_(3)N_(4))is viewed as a promising visible-light photocatalyst for industrialization due to its low processing temperature and high chemical stability.However,serious charge recombination caused by incomplete polymerization during direct calcination of nitrogen-rich precursors significantly limits its photocatalytic performances.To boost charge separation,herein,we propose a rational strategy by constructing a crystalline g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x) isotype heterostructure through the molten salt method.Theoretical calculation reveals that apparent charge-transfer channels are formed between g-C_(3)N_(4) and S-doped g-C_(3)N_(4) layers in the heterostructure.Owing to high crystallinity for decreasing charge recombination and isotype heterostructure for efficient charge transfer,the as-prepared g-C_(3)N_(4)/g-C_(3)N_(4-x)S_(x) showed remarkable photocatalytic performances with the hydrogen production rate elevated by up to 12.3 times of its singular components.Another novelty of this work is we investigated for the first time the piezocatalytic activity of crystalline g-C_(3)N_(4) by characterizing its performance for H2O2 generation and KMnO4 reduction.Strikingly,its superior piezocatalytic performance over components can be further improved by NaBH4 treatment,which is uncovered to enhance the asymmetric structure of crystalline g-C_(3)N_(4) by introducing extra cyano groups and removing partial NHx species in its tri-s-triazine layer structure.This work opens up new strategies for the design of highly efficient polymeric photocatalysts and highlights the piezocatalytic studies of g-C_(3)N_(4).

耐高温两性离子聚合物压裂液的制备与性能

为获得性能优良的高温低伤害聚合物压裂液,采用丙烯酸、丙烯酰胺和阳离子单体为原料合成了成本较低的含羧基的两性离子共聚物压裂液稠化剂PADA,制备了配套的功能性有机钛交联剂TRGWY,在此基础上构建了高温低伤害酸性聚合物压裂液,研究了该压裂液的性能及其影响因素。研究结果表明,PADA具有良好的增黏能力,可在酸性条件下与TRGWY交联形成聚合物冻胶。压裂液的性能与稠化剂结构、压裂液组成和pH值有关。阳离子单体与阴离子单体摩尔分数为5%时所得产物的综合性能较好;组成为0.6%PADA+1.5%TRGWY的压裂液(pH=3～4)具有良好的耐温抗盐性能及破胶性能,可耐温200℃以上,经180℃、170s^(-1)恒温剪切90min后的黏度仍大于60.0mPa·s,可满足高温油气井压裂施工需要。

Monovalent cation perm-selective membranes(MCPMs)"New developments and perspectives

As one of the most typical and promising membrane processes, electrodialysis(ED) technique plays a more and more significant role in industrial separation. Especially, the separation of monovalent cations and multivalent cations is currently a hot topic, which is not only desirable for many industries but also challenging for academic explorations. The main aim of the present contribution is to view the advances of a wide variety of monovalent cation perm-selective membranes(MCPMs) and their preparation technologies including(1) covalent crosslinking,(2) surface modification,(3) polymer blending,(4) electrospinning,(5) nanofiltration alike membrane,and(6) organic–inorganic hybrid. The relevant advantages and disadvantages with respect to some specific cases have been discussed and compared in detail. Furthermore, we elaborately discuss the opportunities and challenges of MCPMs, the fabricating strategies to take and the future perspectives.

Ferroelectric Oxide Nanocomposites with Trimodal Pore Structure for High Photocatalytic Performance

An effective method to improve the photocatalytic performances of powder catalysts is to use the internal electric field from ferroelectrics to separate photogenerated charge carriers.The design and engineering of a complex hetero-junction with a hierarchical pore structure is highly desirable for the efficient application of ferroelectric materials in photocatalysis.Here,we present a novel strategy using two templates to fabricate PbTiO3/TiO2/carbon(PTC)nanocomposites with a tunable microstructure.A hard SiO2 template combined with an ice template followed by an appropriate pyrolysis procedure introduced trimodal(micro-,meso-,macro-)porosity.The as-prepared PTC nanocomposites with optimal mass ratio exhibited excellent photocatalytic and photoelectrochemical performances.PbTiO3/TiO2 annealed at 900 ℃(PTC-900)showed a MB degradation rate of 0.21 and 0.021 min-1 under UV and visible light irradiation,which are,respectively,7.2 and3 times those of pure PbTiO3.The photocurrent density of the composite catalyst is 1.48 mA cm-2 at the potential of 1.0 V versus saturated calomel electrode,and the rates of hydrogen generation of PTC-900 are as high as 2360 and 9.6 μmol h-1 g-1 under UV and visible light irradiation,respectively.More importantly,the simultaneous application of ultrasound-induced mechanical waves further improved the photocatalytic reactivity.This work serves to improve understanding on the design of ferroelectric/piezoelectric photocatalysts with a hierarchical pore structure and also proposes a widely applicable strategy for the fabrication of high-performance micro-nano/nano-nano structures.

Incorporating topographic factors in nonlinear mixed-effects models for aboveground biomass of natural Simao pine in Yunnan,China

A total of 128 Simao pine trees （Pinus kesiya var. langbianensis） from three regions of Pu＇er City, Yunnan Province, People＇s Republic of China, were destructively sampled to obtain tree aboveground biomass （AGB）. Tree variables such as diameter at breast height and total height, and topographical factors such as altitude, aspect of slope, and degree of slope were recorded. We considered the region and site quality classes as the ran- dom-effects, and the topographic variables as the fixed- effects. We fitted a total of eight models as follows： least- squares nonlinear models （BM）, least-squares nonlinear models with the topographic factors （BMT）, nonlinear mixed-effects models with region as single random-effects （NLME-RE）, nonlinear mixed-effects models with site as single random-effects （NLME-SE）, nonlinear mixed-ef- fects models with the two-level nested region and site random-effects （TLNLME）, NLME-RE with the fixed-ef- fects of topographic factors （NLMET-RE）, NLME-SE with the fixed-effects of topographic factors （NLMET-SE）, and TLNLME with the fixed-effects of topographic factors （TLNLMET）. The eight models were compared by modelfitting and prediction statistics. The results showed： model fitting was improved by considering random-effects of region or site, or both. The models with the fixed-effects of topographic factors had better model fitting. According to AIC and BIC, the model fitting was ranked as TLNLME 〉 NLMET-RE 〉 NLME-RE.〉 NLMET-SE 〉 TLNLMET 〉 NLME-SE 〉 BMT 〉 BM. The differences among these models for model prediction were small. The model pre- diction was ranked as TLNLME 〉 NLME-RE 〉 NLME- SE 〉 NLMET-RE 〉 NLMET-SE 〉 TLNLMET 〉 BMT 〉 BM. However, all eight models had relatively high prediction precision （〉90 %）. Thus, the best model should be chosen based on the available data when using the model to predict individual tree AGB.

Boosting Sodium Storage of Fe1?xS/MoS2 Composite via Heterointerface Engineering

Improving the cycling stability of metal sulfide-based anode materials at high rate is of great significance for advanced sodium ion batteries.However,the sluggish reaction kinetics is a big obstacle for the development of high-performance sodium storage electrodes.Herein,we have rationally engineered the heterointerface by designing the Fe1?xS/MoS2 heterostructure with abundant“ion reservoir”to endow the electrode with excellent cycling stability and rate capability,which is proved by a series of in and ex situ electrochemical investigations.Density functional theory calculations further reveal that the heterointerface greatly decreases sodium ion diffusion barrier and facilitates charge-transfer kinetics.Our present findings not only provide a deep analysis on the correlation between the structure and performance,but also draw inspiration for rational heterointerface engineering toward the next-generation high-performance energy storage devices.

Engineering Leaf-Like UiO-66-SO3H Membranes for Selective Transport of Cations

Metal–organic frameworks(MOFs)with angstrom-sized pores are promising functional nanomaterials for the fabrication of cation permselective membranes(MOF-CPMs).However,only a few research reports show successful preparation of the MOF-CPMs with good cation separation performance due to several inherent problems in MOFs,such as arduous selfassembly,poor water resistance,and tedious fabrication strategies.Besides,low cation permeation flux due to the absence of the cation permeation assisting functionalities in MOFs is another big issue,which limits their widespread use in membrane technology.Therefore,it is necessary to fabricate functional MOF-CPMs using simplistic strategies to improve cation permeation.In this context,we report a facile in situ smart growth strategy to successfully produce ultrathin(<600 nm)and leaflike UiO-66-SO3H membranes at the surface of anodic alumina oxide.The physicochemical characterizations confirm that sulfonated angstrom-sized ion transport channels exist in the as-prepared UiO-66-SO3H membranes,which accelerate the cation permeation(~3×faster than non-functionalized UiO-66 membrane)and achieve a high ion selectivity(Na^+/Mg^2+>140).The outstanding cation separation performance validates the importance of introducing sulfonic acid groups in MOF-CPMs.

On Dynamics and Nash Equilibriums of Networked Games

Networked noncooperative games are investigated,where each player(or agent) plays with all other players in its neighborhood. Assume the evolution is based on the fact that each player uses its neighbors current information to decide its next strategy. By using sub-neighborhood, the dynamics of the evolution is obtained. Then a method for calculating Nash equilibriums from mixed strategies of multi-players is proposed.The relationship between local Nash equilibriums based on individual neighborhoods and global Nash equilibriums of overall network is revealed. Then a technique is proposed to construct Nash equilibriums of an evolutionary game from its one step static Nash equilibriums. The basic tool of this approach is the semi-tensor product of matrices, which converts strategies into logical matrices and payoffs into pseudo-Boolean functions, then networked evolutionary games become discrete time dynamic systems.

Gadolinium-incorporated CsPbI_(2)Br for boosting efficiency and long-term stability of all-inorganic perovskite solar cells

All-inorganic CsPbI_(2)Br perovskite solar cells(PSCs)have received extensive research interests recently.Nevertheless,their low efficiency and poor long-term stability are still obstacles for further commercial application.Herein,we demonstrate that high efficiency and exceptional long-term stability are realized by incorporating gadolinium(III)chloride(GdCl_(3))into the CsPbI_(2)Br perovskite film.The incorporation of GdCl_(3) enhances the Goldschmidt tolerance factor of CsPbI_(2)Br perovskite,yielding a dense perovskite film with small grains,thus the a-phase CsPbI_(2)Br is remarkably stabilized.Additionally,it is found that the GdCl_(3)-incorporated perovskite film achieves suppressed charge recombination and appropriate energy level alignment compared with the pristine CsPbI_(2)Br film.The noticeable increment in efficiency from14.01%(control PSC)to 16.24%is achieved for GdCl_(3)-incorporated PSC.Moreover,the nonencapsulated GdCl_(3)-incorporated PSC exhibits excellent environmental and thermal stability,remaining over 91%or90%of the original efficiency after 1200 h aging at 40%relative humidity or 480 h heating at 85℃ in nitrogen glove box respectively.The encapsulated GdCl_(3)-incorporated PSC presents an improved operational stability with over 88%of initial efficiency under maximum power point(MPP)tracking at 45℃ for1000 h.This work presents an effective ion-incorporation approach for boosting efficiency and long-term stability of all-inorganic PSCs.

Epidemiology and Mechanisms of Ceftazidime-Avibactam Resistance in Gram-Negative Bacteria

Carbapenem resistance presents a major challenge for the global public health network, as clinical infections caused by carbapenem-resistant organisms(CRO) are frequently associated with significant morbidity and mortality. Ceftazidime–avibactam(CAZ–AVI) is a novel cephalosporin/β-lactamase inhibitor combination offering an important advance in the treatment of CRO infections. CAZ–AVI has been reported to inhibit the activities of Ambler classes A, C, and some class D enzymes. However, bacterial resistance has been emerging shortly after the introduction of this combination in clinical use, with an increasing trend. Understanding these resistance mechanisms is crucial for guiding the development of novel treatments and aiding in the prediction of underlying resistance mechanisms. This review aims to systematically summarize the epidemiology of CAZ–AVI-resistant strains and recently identified resistance mechanisms of CAZ–AVI, with a focus on the production of β-lactamase variants, the hyperexpression of β-lactamases, reduced permeability, and overexpressed efflux pumps. The various mechanisms of CAZ–AVI resistance that have emerged within a short timescale emphasize the need to optimize the use of current agents, as well as the necessity for the surveillance of CAZ–AVI-resistant pathogens.

Chinese Anti-Cancer Association as a non-governmental organization undertakes systematic cancer prevention work in China

Cancer has become the first leading cause of death in the world, particularly in low- and middle-income countries. Facing the increasing trend of cancer incidence and mortality, China issued and implemented ＂three-early（early prevention, early diagnosis and early treatment）＂ national cancer prevention plan. As the main body and dependence of social governance, non-governmental organizations（NGOs） take over the role of government in the field of cancer prevention and treatment. American Cancer Society（ACS） made a research on cancer NGOs and civil society in cancer control and found that cancer NGOs in developing countries mobilize civil society to work together and advocate governments in their countries to develop policies to address the growing cancer burden. Union for International Cancer Control（UICC）, Cancer Council Australia（CCA）, and Malaysian cancer NGOs are the representatives of cancer NGOs in promoting cancer control. Selecting Chinese Anti-Cancer Association（CACA） as an example in China, this article is to investigate how NGOs undertake systematic cancer prevention work in China. By conducting real case study, we found that, as a NGO, CACA plays a significant role in intensifying the leading role of government in cancer control, optimizing cancer outcomes, decreasing cancer incidence and mortality rates and improving public health.

Catalytic kinetics of dimethyl ether one-step synthesis over CeO_2–CaO–Pd/HZSM-5 catalyst in sulfur-containing syngas process

CeO_2–CaO–Pd/HZSM-5 catalyst was prepared for the dimethyl ether(DME) one-step synthesis in a continuous fixed-bed micro-reactor from the sulfur-containing syngas. The catalytic stability over hybrid catalyst of CeO_2–CaO–Pd/HZSM-5 was investigated to ensure that the kinetics experimental results were not significantly influenced by induction period and catalytic deactivation. A large number of kinetic data points(40 sets) were obtained over a range of temperature(240–300 °C), pressure(3–4 MPa), gas hourly space velocity(GHSV)(2000–3000 L·kg^(-1)·h^(-1)) and H_2/CO mole ratio(2–3). Kinetic model for the methanol synthesis reaction and the dehydration of methanol were obtained separately according to reaction mechanism and Langmuir–Hinshelwood mechanism. Regression parameters were investigated by the method combining the simplex method and Runge–Kutta method. The model calculations were in appropriate accordance with the experimental data.

Fabricating Na/In/C Composite Anode with Natrophilic Na-In Alloy Enables Superior Na Ion Deposition in the EC/PC Electrolyte

In conventional ethylene carbonate(EC)/propylene carbonate(PC)electrolyte,sodium metal reacts spontaneously and deleteriously with solvent molecules.This significantly limits the practical feasibility of high-voltage sodium metal batteries based on Na metal chemistry.Herein,we present a sodium metal alloy strategy via introducing NaIn and Na_(2)In phases in a Na/In/C composite,aiming at boosting Na ion deposition stability in the common EC/PC electrolyte.Symmetric cells with Na/In/C electrodes achieve an impressive long-term cycling capability at 1 mA cm^(-2)(>870 h)and 5 mA cm^(-2)(>560 h),respectively,with a capacity of 1 mAh cm^(-2).In situ optical microscopy clearly unravels a stable Na ion dynamic deposition process on the Na/In/C composite electrode surface,attributing to a dendrite-free and smooth morphology.Furthermore,theoretical simulations reveal intrinsic mechanism for the reversible Na ion deposition behavior with the composite Na/In/C electrode.Upon pairing with a highvoltage NaVPOF cathode,Na/In/C anode illustrates a better suitability in SMB s.This work promises an alternative alloying strategy for enhancing Na metal interfacial stability in the common EC/PC electrolyte for their future applications.

Two-Layer Contact Nonlinear Mechanical Analysis of Flexible Drilling Tool in the Wellbore

The lack of research on flexible drilling tool leads to limited application of ultra-short radius horizontal wells.The flexible drilling tool is different from the conventional drilling tool.The flexible drilling pipe involves a mutual transition between the structure and the mechanism during the deformation process.At the same time,the flexible drilling pipe and the eccentric guide tube,the guide tube and the wellbore generate random contact.In this paper,3-D beam elements,universal joint elements,rigid beam elements and the beam-beam contact elements are combined to establish a two-layer contact nonlinear finite element model of the flexible drilling tool in the wellbore.The dynamic relaxation method is introduced for numerical solution.The feasibility of the model and the algorithm is verified by an example.The mechanical analysis of flexible drilling tool under the four hole inclinations in the oblique section is carried out.It is found that the flexible drilling pipe has a“folded line”deformation.The contact force between the flexible drilling pipe and the guide tube is randomly distributed.The contact force between the guide tube and the wellbore in the oblique section is greater than that in the vertical section.As the hole inclinations increase,the torque and axial force transmitted to the drill bit gradually decrease.

TWO-DIMENSIONAL VISUALIZATION OF THE PROPAGATION SPEED OF CORTICAL SPREADING DEPRESSION IN RAT CORTEX

Cortical spreading depression(CSD),which is a significant pathological phenomenon that correlates with migraines and cerebral ischemia,has been characterized by a wave of depolarization among neuronal cells and propagates across the cortex at a rate of 2–5mm/min.Although the propagation pattern of CSD was well-investigated using high-resolution optical imaging technique,the variation of propagation speed of CSD across different regions of cortex was not well-concerned,partially because of the lack of ideal approach to visualize two-dimensional distribution of propagation speed of CSD over the whole imaged cortex.Here,we have presented a method to compute automatically the propagation speed of CSD throughout every spots in the imaged cortex.In this method,temporal clustering analysis(TCA)and least square estimation(LSE)were first used to detect origin site where CSD was induced.Taking the origin site of CSD as the origin of coordinates,the data matrix of each image was transformed into the corresponding points based on the polar-coordinate representation.Then,two fixed-distance regions of interest(ROIs)are sliding along with the radial coordinate at each polar angle within the image for calculating the time lag with correlating algorithm.Finally,we could draw a twodimensional image,in which the value of each pixel represented the velocity of CSD when it spread through the corresponding area of the imaged cortex.The results demonstrated that the method can reveal the heterogeneity of propagation speed of CSD in the imaged cortex with high fidelity and intuition.

A Serological Survey of Contagious Caprine Pleuropneumonia in Taizhou City,Jiangsu Province

[ Objective] This study aimed to investigate the prevalence of contagious caprine pleuropneumonia in Taizhou City, Jiangsu Province. [ Method] By using indirect hemagglutination assay kits for detection of antibodies against Mycoplasma capricolum subsp, capripneumoniae （ Mecp）, Mycoplasma mycoides subsp. capriclonum （Mmc） and Mycopalsam ovipneumonia （ Movi）, 1 157 goat sera from Taizhou City of Jiangsu Province were detected. [ Result ] The average positive detection rate of Mccp and Mmc in infected goats was 51.85% and 39.81%, respectively; the average positive detection rate of Mccp and Mmc in non-infected goats was 10.52% and 5.84%, respectively, and the total positive detection rate of Mycoplasma infections was 16.37%. [ Conclusion ] Mycoplasma infections oc- cur commonly in Taizhou City. The prevention and control of Mycoplasma infections should be strengthened.

Topology modulation of tetraphenylethylene graphdiyne at a liquid-liquid interface

Monomers with low symmetries can form different topological structures in the preparation of organic two-dimensional(2D)materials.However,it remains challenging to modulate the topologies in practical synthesis.Leveraging theoretical insights into the formation energy of potential structural configurations,we report the topology modulation of a graphdiyne(GDY)derivative constructed from two-fold symmetric tetrakis(4-ethynylphenyl)ethene precursor by changing solvent combinations in a liquid-liquid interfacial system.An aqueous-organic(water-dichloromethane)interface afforded GDY with a kagome topology while a rhombic topology was formed at an organic-organic(hexane-acetonitrile)interface.A comprehensive evaluation of their structures and optoelectronic properties was conducted through various characterization techniques and theoretical computations.Our study provided new insights to modulate the topology of not only GDY but also other framework structures and obtain topologically pure materials in situations where different topologies are possible during practical synthesis.

Enhancing source domain availability through data and feature transfer learning for building power load forecasting

During the initial phases of operation following the construction or renovation of existing buildings,the availability of historical power usage data is limited,which leads to lower accuracy in load forecasting and hinders normal usage.Fortunately,by transferring load data from similar buildings,it is possible to enhance forecasting accuracy.However,indiscriminately expanding all source domain data to the target domain is highly likely to result in negative transfer learning.This study explores the feasibility of utilizing similar buildings(source domains)in transfer learning by implementing and comparing two distinct forms of multi-source transfer learning.Firstly,this study focuses on the Higashita area in Kitakyushu City,Japan,as the research object.Four buildings that exhibit the highest similarity to the target buildings within this area were selected for analysis.Next,the two-stage TrAdaBoost.R^(2) algorithm is used for multi-source transfer learning,and its transfer effect is analyzed.Finally,the application effects of instance-based(IBMTL)and feature-based(FBMTL)multi-source transfer learning are compared,which explained the effect of the source domain data on the forecasting accuracy in different transfer modes.The results show that combining the two-stage TrAdaBoost.R^(2) algorithm with multi-source data can reduce the CV-RMSE by 7.23%compared to a single-source domain,and the accuracy improvement is significant.At the same time,multi-source transfer learning,which is based on instance,can better supplement the integrity of the target domain data and has a higher forecasting accuracy.Overall,IBMTL tends to retain effective data associations and FBMTL shows higher forecasting stability.The findings of this study,which include the verification of real-life algorithm application and source domain availability,can serve as a theoretical reference for implementing transfer learning in load forecasting.

同质园环境和遗传分化影响锦鸡儿属植物根际土壤固氮菌多样性和群落结构

环境和遗传分化共同影响植物的功能性状,进而能够通过根系分泌物影响根际微生物。本研究利用同质园试验,通过高通量测序技术,基于固氮酶基因nifH的同源性,分析同质园栽培的不同种源小叶锦鸡儿(Caragana microphylla)、中间锦鸡儿(C.liouana)和荒漠锦鸡儿(C.roborovskyi)根际土壤固氮菌多样性,并探究其与种源地气候及同质园土壤属性的关系。结果表明,3种锦鸡儿植物根际土壤固氮菌隶属6门9纲18目21科33属72种,其中变形菌门、疣微菌门和蓝细菌门为优势门,优势属为中慢生根瘤菌属(Mesorhizobium)、固氮氢自养单胞菌属(Azohydromonas)和慢生根瘤菌属(Bradyrhizobium)。3种锦鸡儿根际土壤固氮菌α多样性种间差异不显著,但中间锦鸡儿和荒漠锦鸡儿根际土壤固氮菌的α多样性存在显著的种内差异(P<0.05),小叶锦鸡儿和荒漠锦鸡儿根际土壤固氮菌群落结构存在显著的种内差异(P<0.05)。冗余分析表明同质园土壤pH和种源地年均温分别是影响3种锦鸡儿根际土壤固氮菌多样性和群落结构变化的主要因子,说明3种锦鸡儿属植物根际土壤固氮菌群落多样性受同质园环境与遗传分化的共同调控。本研究结果为锦鸡儿属植物的生态适应机制和引种栽培提供理论依据和数据支持。