Bose–Einstein distribution temperature features of quasiparticles around magnetopolaron in Gaussian quantum wells of alkali halogen ions

We have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum wells.The obtained results showed that under magnetic field effect,magnetopolaron quasiparticle was formed through the interaction of electrons and surrounding phonons.At the same time,magnetopolaron was influenced by phonon temperature statistical law and important energy level shifts down and binding energy increases.This revealed that lattice temperature and magnetic field could easily affect magnetopolaron and the above results could play key roles in exploring thermoelectric conversion and conductivity of crystal materials.

Oxygen-vacancy-rich MnO_(x)supported RuO_(x)for efficient base-free oxidation of 5-hydroxymethylfurfural and 5-methoxymethylfurfural to 2,5-furandicarboxylic acid

2,5-Furandicarboxylic acid(FDCA)is a promising biomass-derived polymeric monomer that serves as an attractive alternative to terephthalic acid derived from fossil resources.However,the green and efficient production of FDCA through the oxidation of 5-hydroxymethylfurfural(HMF)and its derivatives is still rudimentary under base-free conditions.In this work,oxygen-vacancy-rich Mn Oxwas prepared and displayed a strong adsorption and anchoring ability to Ru species that mainly exposed the(210)plane of RuO_(2),bringing about highly dispersed and active interfacial Ru-O-Mn structures.Experimental results and density functional theory calculations confirm that these above features greatly facilitate the adsorption/activation of oxygen and the dehydrogenation-oxidation of HMF/5-methoxymethylfurfural(MMF),which enables an efficient FDCA production under base-free and mild conditions.Notably,a desirable FDCA yield of 86.56%was still obtained from concentrated HMF(10 wt%)under base-free conditions over oxygen-vacancy-rich Mn Oxsupported Ru Ox(1.0 MPaO_(2),120℃,6 h).This work delineates a facile catalyst preparation strategy for HMF/MMF oxidation,and might open a new avenue for the green synthesis of FDCA under base-free conditions.

Study on synergistic leaching of potassium and phosphorus from potassium feldspar and solid waste phosphogypsum via coupling reactions

To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.

CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose

The conversion of biomass into sugar platform compounds is very important for the biorefinery industry.Pretreatment is essential to the biomass of the sugar platform,however,the lignin obtained by pretreatment,as a key part of lignocellulose,generally has a passive effect on the enzymatic hydrolysis of cellulose into sugars.In this study,p-TsOH(p-toluenesulfonic acid),DES(Deep eutectic solvent)and CAOSA(cooking with active oxygen and solid alkali)pretreatment ways were used to fraction lignin from bamboo biomass.After CAOSA treatment,the hydrolysis efficiency of the pulp was 95.57%.Moreover,the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis system.In this work,the results showed that CAOSA-extracted lignin with lower D(1.31-1.25)had a better adsorption effect on the enzyme protein.p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic hydrolysis.In addition,the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification.

Behavior of exciton in direct−indirect band gap Al_(x)Ga_(1−x)As crystal lattice quantum wells

Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is also found to influence the study of exciton ground state energy and ground state binding energy in Al_(x)Ga_(1−x)As semiconductor spherical quantum dots.The Al_(x)Ga_(1−x)As is considered to be a direct semiconductor at AI concentration below 0.45,and an indirect one at the concentration above 0.45.With regards to the former,the ground state binding energy increases and decreases with AI concentration and eigenfrequency,respectively;however,while the ground state energy increases with AI concentration,it is marginally influenced by eigenfrequency.On the other hand,considering the latter,while the ground state binding energy increases with AI concentration,it decreases with eigenfrequency;nevertheless,the ground state energy increases both with AI concentration and eigenfrequency.Hence,for the better practical performance of the semiconductors,the properties of the excitons are suggested to vary by adjusting AI concentration and eigenfrequency.

地方高校选修课程考核模式的改革与探索——以汉江师范学院为例

课程考核是课程教学中提高教学质量和评价人才培养质量的重要环节及有效手段。然而,地方高校汉江师范学院选修课程仍然存在考核方式单一、学生积极性差、创新性不足的问题。本文对选修课程考核模式进行了改革与探索,以表面活性剂化学课程为例,从教师评价、学生互评、学生贡献等三个角度出发,以科学成才观念为核心,设计并实践了教师评价(代号“T”)、组组互评(代号“G”)、个人贡献比(代号“I”)的“TGI”考核模式,打破传统的考核方式,提高学生积极性与主动性,激发学生的创新性,活化学生创新思维,培养学生的综合能力。“TGI”考核模式对提高课程教学质量具有重要的意义,对其他选修课程考核评价具有一定的借鉴作用。

One-pot synthesis of 2,5-bis(hydroxymethyl)furan from biomass derived 5-(chloromethyl)furfural in high yield

5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated for the first time.A 91%BHMF yield was obtained over Ru/Cu Oxcatalyst,and BHMF was mainly produced by the consecutive hydrolysis and hydrogenation of CMF with 5-hydroxymethylfurfural(HMF)as an intermediate.Kinetic studies revealed that the conversion of HMF to BHMF was the rate-determining step.Remarkably,the characterizations and density functional theory(DFT)calculations further revealed the lower electron density of Ru NPs in Ru/Cu Oxcatalyst,resulting in a larger adsorption energy and a smaller free energy difference for the formation of alcohols.The present findings offered a new pathway for biomass-derived diol production through CMF as a potential source.

Heterogeneously-catalyzed aerobic oxidation of furfural to furancarboxylic acid with CuO-Promoted MnO_(2)

A cost-effective and sustainable noble-metal free catalyst system based on ubiquitously available Mn-Cu bimetallic oxides was served as efficient catalysts for furfural selective oxidation to furancarboxylic acid(FA). Interestingly, Mn_(2)Cu_(1)O_(x)exhibited an excellent furfural conversion of 99% with quantitative selectivity toward FA. Especially, we demonstrate the significant weakening of the Mn-O bonds with the incorporation of CuO into the Mn-Cu oxides, resulting in an improved OLreactivity of Mn_(2)Cu_(1)O_(x), which brings about a higher catalytic activity for furfural oxidation. More importantly, Mn_(2)Cu_(1)O_(x)could exhibit YFA>90% over 5 cycles of reusability test. Through this study, the relationship between the morphology, surface chemistry, and catalytic activity of Mn-Cu bimetallic oxides are elucidated, providing a simple and environmentally friendly catalytic strategy and scientific basis for the development of Mn-Cu bimetallic oxides bioderived molecular aerobic oxidation materials.

Post-dilatation improves stent apposition in patients with ST-segment elevation myocardial infarction receiving primary percutaneous intervention: A multicenter, randomized controlled trial using optical coherence tomography

BACKGROUND: Stent failure is more likely in the lipid rich and thrombus laden culprit lesions underlying ST-segment elevation myocardial infarction(STEMI).This study assessed the effectiveness of post-dilatation in primary percutaneous coronary intervention(pPCI) for acute STEMI.METHODS: The multi-center POST-STEMI trial enrolled 41 consecutive STEMI patients with symptom onset <12 hours undergoing manual thrombus aspiration and Promus Element stent implantation.Patients were randomly assigned to control group(n=20) or post-dilatation group(n=21) in which a non-compliant balloon was inflated to >16 atm pressure.Strut apposition and coverage were evaluated by optical coherence tomography(OCT) after intracoronary verapamil administration via thrombus aspiration catheter, post pPCI and at 7-month follow-up.The primary endpoint was rate of incomplete strut apposition(ISA) at 7 months after pPCI.RESULTS: There were similar baseline characteristics except for stent length(21.9 [SD 6.5] mm vs.26.0 [SD 5.8] mm, respectively, P=0.03).In post-dilatation vs.control group, ISA rate was lower(2.5% vs.4.5%, P=0.04) immediately after pPCI without affecting final TIMI flow 3 rate(95.2% vs.95.0%, P>0.05) or corrected TIMI frame counts(22.6±9.4 vs.22.0±9.7, P>0.05); and at 7-month follow-up(0.7% vs.1.8%, P<0.0001), the primary study endpoint, with similar strut coverage(98.5% vs.98.4%, P=0.63) and 1-year rate of major adverse cardiovascular events(MACE).CONCLUSION: In STEMI patients, post-dilatation after stent implantation and thrombus aspiration improved strut apposition up to 7 months without affecting coronary blood flow or 1-year MACE rate.Larger and longer term studies are warranted to further assess safety(Clinical Trials.gov identifier: NCT02121223).

蜂巢约束系统边坡防雨水侵蚀特性研究

路基边坡的稳定性是路基安全的重要指标。本文通过试验模拟边坡滑动以及边坡冲蚀,对比附加蜂巢约束前后边坡稳定性的变化来研究蜂巢约束系统边坡防雨水侵蚀特性。试验发现,附加蜂巢后边坡冲蚀量大幅下降,最大可达40%。相同冲蚀时间下,附加蜂巢约束的边坡冲蚀量随流量增加速度较慢,冲蚀速率下降5%~15%;釆用绕流雷诺数分析判断水流的流态,发现雷诺数均大于取定的下临界雷诺数,判断坡面薄层水流为紊流。且有蜂巢约束时,弗汝德数小于1,属于缓流;而在无蜂巢约束系统时,其值大于1,属于急流。结果表明,蜂巢约束可以有效缓解降雨对边坡的侵蚀作用。

N-acetylcysteine attenuates reactive-oxygen-speciesmediated endoplasmic reticulum stress during liver ischemia-reperfusion injury

AIM: To investigate the effects of N-acetylcysteine (NAC) on endoplasmic reticulum (ER) stress and tissue injury during liver ischemia reperfusion injury (IRI).

飞秒激光辅助超声乳化吸除联合多焦点IOL植入术治疗白内障

目的:探讨飞秒激光辅助超声乳化吸除联合多焦点IOL植入术治疗白内障的临床价值。方法:将2015-07/2018-07收治的94例94眼白内障患者以随机数字表法分为观察组47例47眼,对照组47例47眼,观察组行飞秒激光辅助超声乳化吸除联合多焦点IOL植入术治疗,对照组行传统超声乳化吸除联合多焦点IOL植入术治疗,对两组手术相关指标、角膜内皮细胞密度、视力情况及并发症进行观察。结果:观察组超声乳化时间较对照组短,超声能量、术中超声乳化累积能量复合参数及术后7d前房闪辉值均低于对照组(P<0.05)。术前两组角膜内皮细胞密度无差异(P>0.05),术后3mo观察组角膜内皮细胞密度较对照组高(P<0.05)。术前两组BCVA、UCVA无差异(P>0.05),术后3mo观察组BCVA及UCVA均优于对照组(P<0.05)。两组并发症无差异(P>0.05)。结论:飞秒激光辅助超声乳化吸除联合多焦点IOL植入术治疗白内障临床效果明显,能减少超声累积释放能量,减轻角膜内皮损伤,促进患者视力恢复,安全性高。

CSF-ctDNA与TIF-ctDNA检测在脑胶质瘤中的临床应用研究

目的:探讨脑脊液(cerebrospinal fluid,CSF)来源的循环肿瘤DNA(circulating tumor DNA,ctDNA)与肿瘤间质液(tumor interstitial fluid,TIF)ctDNA检测在脑胶质瘤中的诊断、复发监测、肿瘤标志物及靶向药物筛选方面的应用价值。方法:收集2019年1月至12月河南省人民医院12例脑胶质瘤患者CSF标本、TIF标本及血液标本。CSF标本、TIF标本进行二代基因测序(next generation sequencing,NGS)检测ctDNA突变,血液标本进行白细胞胚系突变检测,二者对比筛选出肿瘤突变基因。与临床资料结合,对胶质瘤患者CSF-ctDNA与TIF-ctDNA检测结果进行对比及生物信息学分析。结果:检测到57种基因变异类型共209个,标本总平均突变数为8.7个,CSF-ctDNA平均突变数为4.3个,TIF-ctDNA平均突变数为13个。9例CSF-ctDNA检测阳性率为(75.0%)、11例TIF-ctDNA检测阳性率(91.6%)。同1例患者ctDNA浓度TIF标本高于CSF标本,TIF标本ctDNA平均浓度(3.38 ng/μL)高于CSF标本中ctDNA平均浓度(0.58 ng/μL)。ctDNA检测发现肿瘤基因突变,较影像学发现复发时间平均提前2.9个月。突变基因PIK3CA、PTEN、KRAS、EGFR、TP53、NF1、BRCA1、BRCA2、TSC1、TSC2、IDH1、CDKN2A匹配到靶向潜在获益药物,突变基因PIK3CA、KRAS、EGFR匹配到潜在耐药药物。结论:CSF-ctDNA与TIF-ctDNA能够比影像学更早发现肿瘤复发,是一种可行的能够在肿瘤的发生和复发的过程反复检测、筛选胶质瘤标志物的方法,对胶质瘤患者基因诊断及靶向治疗有一定临床指导作用。相对于CSF-ctDNA,TIF-ctDNA检测获得样本ctDNA浓度更高,检测患者基因平均突变数更多、检测阳性率与检测效力更高,能够提供更多、全面的肿瘤基因组信息,适合临床用于获取胶质瘤的基因表达信息。

Effect of borneol and electroacupuncture on the distribution of hyperforin in the rat brain

Hyperforin is an antidepressant drug that has unstable therapeutic effects, due to its poor ability to cross the blood-brain barrier. Borneol and electroacupuncture have both been found to increase the permeability of the blood-brain barrier. As such, the current study examined the distribution of hyperforin in the rat brain, and the effects on the brain distribution of hyperforin of borneol alone （orally administered）, and borneol combined with electroacupuncture treatment. High-performance liquid chromatography technology and pharmacokinetic analysis revealed that treatment with borneol alone （300, 600 mg/kg） increased peak concentration and the area under the curve for hyperforin in the brain. In addition, the bioavailability of hyperforin in rat brain increased by 42.7%. However, increasing the dose of borneol dose did not appear to increase the distribution of hyperforin in the brain. Importantly, applying electroacupuncture at Baihui （GV 20） or Yamen （GV 15） appeared to enhance the brain-delivery effects of borneol, although this effect was weak. Overall, our results indicated that borneol alone or combined with electroacupuncture can provide promising strategies for brain-targeted delivery in central nervous system therapy.

A Robustness Analysis of CMIP5 Models over the East Asia-Western North Pacific Domain

The Coupled Model Intercomparison Project （CMIP） is an international community-based infrastructure that supports climate model intercomparison, climate variability, climate prediction, and climate projection. Improving the performance of climate models over East Asia and the western North Pacific has been a challenge for the climate-modeling community. In this paper, we provide a synthesis robustness analysis of the climate models participating in CMIP-Phase 5 （CMIP5）. The strengths and weaknesses of the CMIP5 models are assessed from the perspective of climate mean state, interannual variability, past climate change during the mid-Pliocene （MP） and the last millennium, and climate projection. The added values of regional climate models relative to the driving global climate models are also assessed. Although an encouraging increase in credibility and an improvement in the simulation of mean states, interannual variability, and past climate changes are visible in the progression from CMIP3 to CMIPS, some previously noticed biases such as the ridge position of the western North Pacific subtropical high and the associated rainfall bias are still evident in CMIP5 models. Weaknesses are also evident in simulations of the interannual amplitude, such as El Nino- Southern Oscillation （ENSO）-monsoon relationships. Coupled models generally show better results than standalone atmospheric models in simulating both mean states and interannual variability. Multi-model intercomparison indicates significant uncertainties in the future projection of climate change, although precipitation increases consistently across models constrained by the Clausius-Clapeyron relation. Regional ocean-atmosphere coupled models are recommended for the dynamical downscaling of climate change oroiections over the East Asia-western North Pacific domain.

The influence of borehole arrangement of soundless cracking demolition agents(SCDAs)on weakening the hard rock

The hard roof difficult to collapse easily causes gas accumulation,which threatens the production safety of coal mine.Therefore,roof pre-cracking is required.Although blasting and hydraulic fracturing can also crack the roof,blasting can easily induce rock bursts,whereas hydraulic fracturing needs complex equipment.In contrast,soundless cracking demolition agents(SCDAs)with noise-free,dust-free,and safe characteristics have obvious advantages.The main component of SCDA is calcium oxide,which reacts with water to produce higher expansion pressure.In this paper,focused on the angles of the borehole,the effect of SCDA is analyzed by numerical simulation based on Pingdingshan coal mine.The research results showed that the azimuthal angle a(between borehole projection and the roadway direction)does not significantly affect the efficacy of SCDAs,whereas the influence of borehole elevation angle b is far more significant than that of the azimuthal angle.Therefore,the angle b is a dominant factor influencing the effect of SCDAs.Based on different effects of SCDAs at different angle of boreholes,the weakening unit was established,so the SCDAs could give full play to roof fracturing.Moreover,field tests validated the importance of borehole angle on weakening the hard roofs.

Optimal Operation of Integrated Heat and Electricity Systems:A Tightening McCormick Approach

Combined heat and electricity operation with variable mass flow rates promotes flexibility,economy,and sustainability through synergies between electric power systems(EPSs)and district heating systems(DHSs).Such combined operation presents a highly nonlinear and nonconvex optimization problem,mainly due to the bilinear terms in the heat flow model—that is,the product of the mass flow rate and the nodal temperature.Existing methods,such as nonlinear optimization,generalized Benders decomposition,and convex relaxation,still present challenges in achieving a satisfactory performance in terms of solution quality and computational efficiency.To resolve this problem,we herein first reformulate the district heating network model through an equivalent transformation and variable substitution.The reformulated model has only one set of nonconvex constraints with reduced bilinear terms,and the remaining constraints are linear.Such a reformulation not only ensures optimality,but also accelerates the solving process.To relax the remaining bilinear constraints,we then apply McCormick envelopes and obtain an objective lower bound of the reformulated model.To improve the quality of the McCormick relaxation,we employ a piecewise McCormick technique that partitions the domain of one of the variables of the bilinear terms into several disjoint regions in order to derive strengthened lower and upper bounds of the partitioned variables.We propose a heuristic tightening method to further constrict the strengthened bounds derived from the piecewise McCormick technique and recover a nearby feasible solution.Case studies show that,compared with the interior point method and the method implemented in a global bilinear solver,the proposed tightening McCormick method quickly solves the heat–electricity operation problem with an acceptable feasibility check and optimality.

Characterization of flavor fingerprinting of red sufu during fermentation and the comparison of volatiles of typical products

Traditional Chinese red sufu is a popular condiment,and typical flavor is an important indicator of sensory qualities in commercial products.In this study,the volatile aroma analysis of Wangzhihe red sufu(WRS)from different fermentation stages and four typical red sufu products from different locations was carried out by gas chromatography-mass spectrometry(GC–MS),gas chromatography-mass spectrometry/olfactory(GC–MS/O),electronic nose(E-nose)and sensory evaluation.Results showed that 106 volatile compounds were identified in Wangzhihe red sufu during fermentation process,in which phenolics and alcohols were dominant at molded and salted phetze stages,while esters and alcohols became predominate at post-fermentation stage.The volatile aroma substances varied at each fermentation stage.Furthermore,86 volatiles,including 16 aroma-active compounds,were detected in four typical red sufu products.The multivariate analysis results showed the difference in samples from different fermentation stages and typical red sufu products according to GC–MS and E-nose analysis.Combined with flavor omics,discriminant model was established for effective discrimination of samples from different fermentation stages and locations,as well as references to sufu maturity extent.The study presented a new strategy for quality evaluation of red sufu,which could be the supplement to quality evaluation standards.

Efficient and stable wireless power transfer based on the non-Hermitian physics

As one of the most attractive non-radiative power transfer mechanisms without cables,efficient magnetic resonance wireless power transfer(WPT)in the near field has been extensively developed in recent years,and promoted a variety of practical applications,such as mobile phones,medical implant devices and electric vehicles.However,the physical mechanism behind some key limitations of the resonance WPT,such as frequency splitting and size-dependent efficiency,is not very clear under the widely used circuit model.Here,we review the recently developed efficient and stable resonance WPT based on non-Hermitian physics,which starts from a completely different avenue(utilizing loss and gain)to introduce novel functionalities to the resonance WPT.From the perspective of non-Hermitian photonics,the coherent and incoherent effects compete and coexist in the WPT system,and the weak stable of energy transfer mainly comes from the broken phase associated with the phase transition of parity-time symmetry.Based on this basic physical framework,some optimization schemes are proposed,including using nonlinear effect,using bound states in the continuum,or resorting to the system with high-order parity-time symmetry.Moreover,the combination of non-Hermitian physics and topological photonics in multi-coil system also provides a versatile platform for long-range robust WPT with topological protection.Therefore,the non-Hermitian physics can not only exactly predict the main results of current WPT systems,but also provide new ways to solve the difficulties of previous designs.

The FGOALS climate system model as a modeling tool for supporting climate sciences:An overview

Climate system models are useful tools for understanding the interactions among the components of the climate system and predicting/projecting future climate change. The development of climate models has been a central focus of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences(LASG/IAP) since the establishment of the laboratory in 1985. In China, many pioneering component models and fully coupled models of the climate system have been developed by LASG/IAP. The fully coupled climate system developed in the recent decade is named FGOALS(Flexible Global Ocean-Atmosphere-Land System Model). In this paper, an application-oriented review of the LASG/IAP FGOALS model is presented. The improved model performances are demonstrated in the context of cloud-radiation processes, Asian monsoon, ENSO phenomena, Atlantic Meridional Overturning Circulation(AMOC) and sea ice. The FGOALS model has contributed to both CMIP5(Coupled Model Intercomparison Project-phase 5) and IPCC(Intergovernmental Panel on Climate Change) AR5(the Fifth Assessment Report). The release of FGOALS data has supported the publication of nearly 500 papers around the world. The results of FGOALS are cited ~106 times in the IPCC WG1(Working Group 1) AR5. In addition to the traditional long-term simulations and projections, near-term decadal climate prediction is a new set of CMIP experiment, progress of LAGS/IAP in the development of nearterm decadal prediction system is reviewed. The FGOALS model has supported many Chinese national-level research projects and contributed to the national climate change assessment report. The crucial role of FGOALS as a modeling tool for supporting climate sciences is highlighted by demonstrating the model's performances in the simulation of the evolution of Earth's climate from the past to the future.