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.

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

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 nal TIMI ow 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 ow or 1-year MACE rate. Larger and longer term studies are warranted to further assess safety.

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。

CuO_x-CaCO_3催化剂高效催化生物质乙酰丙酸甲酯制备γ-戊内酯（英文）

γ-戊内酯(GVL)在燃料和化学品上有着巨大的潜在利用价值,如何从生物质木质纤维素出发经济地制备GVL广受关注.目前已有大量的研究致力于利用不同氢源从乙酰丙酸及其酯类催化加氢制备GVL的催化体系.过去的数年里,外加氢气条件下的乙酰丙酸及其酯类加氢制备GVL已经得到了广泛的研究.考虑到液体醇使用和管理相比于氢气更为安全便捷,而且醇类如甲醇、乙醇都是可以从生物质制备的绿色环保的溶剂,利用醇类通过Meerwein-Ponndorf-Verley(MPV)还原作为生物质催化加氢过程中的的溶剂和氢供体已经引起了人们的浓厚兴趣.在脂肪醇中,甲醇的还原势能最高,在MPV还原里的效果不如其他醇,但可以通过甲醇重整制氢的方式来供氢.此外,乙酰丙酸甲酯(ML)可以通过甲醇中酸催化醇解碳水化合物制得,因此可以尝试将碳水化合物醇解制备ML;甲醇重整制氢以及ML加氢结合起来,从而省去繁琐且能耗较大的ML分离步骤.腐殖质的存在和固体催化剂在甲醇中的稳定性是上述两步法策略的最大挑战.本文通过草酸凝胶共沉淀法首次制备了(n)CuO_x-CaCO_3(n为Cu/Ca摩尔比)双功能催化剂,用于以甲醇为原位氢源,从生物质ML一锅制备GVL反应中.经筛选,(3/2)CuO_x-CaCO_3催化制备GVL的得率高达95.6%.利用各种表征手段分析了催化剂使用前后的组成和结构变化.结果显示,新制的CuO_x-CaCO_3催化剂中即可检测到Cu+的存在,且在使用过程中CaCO_3可以有效阻止二价铜在氢气氛围下被完全还原成单质铜.对于该体系中的ML加氢,亚铜有着比单质铜更佳的催化性能.循环实验表明,(3/2)CuO_x-CaCO_3至少可以连续稳定使用8次,其催化活性没有明显损失.此外,在纤维素醇解产物中存在腐殖质的情况下,(3/2)CuO_x-CaCO_3催化剂仍能够有效催化纤维素醇解得到的ML加氢制备GVL.因此可以利用这个高效廉价的催化剂开发一种便捷的一锅两步法从木质纤维素生物质制备GVL,即将酸催化的纤维素醇解、甲醇重整、ML在甲醇溶剂中加氢三者整合起来.

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).METHODS:Mice were injected with NAC(300 mg/kg) intraperitoneally 2 h before ischemia.Real-time polymerase chain reaction and western blotting determined ER stress molecules(GRP78,ATF4 and CHOP).To analyze the role of NAC in reactive oxygen species(ROS)-mediated ER stress and apoptosis,lactate dehydrogenase(LDH) was examined in cultured hepatocytes treated by H2O2 or thapsigargin(TG).RESULTS:NAC treatment significantly reduced the level of ROS and attenuated ROS-induced liver injury after IRI,based on glutathione,malondialdehyde,serum alanine aminotransferase levels,and histopathology.ROS-mediated ER stress was significantly inhibited in NAC-treated mice.In addition,NAC treatment significantly reduced caspase-3 activity and apoptosis after reperfusion,which correlated with the protein expression of Bcl-2 and Bcl-xl.Similarly,NAC treatment significantly inhibited LDH release from hepatocytes treated by H2O2 or TG.CONCLUSION:This study provides new evidence for the protective effects of NAC treatment on hepatocytes during IRI.Through inhibition of ROS-mediated ER stress,NAC may be critical to inhibit the ER-stressrelated apoptosis pathway.

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.

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.

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.

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.

Geochronological,geochemical,and Nd-Hf isotopic studies of the Qinling Complex,central China:Implications for the evolutionary history of the North Qinling Orogenic Belt

The Qinling Complex of central China is thought to be the oldest rock unit and the inner core of the North Qinling Orogenic Belt （NQOB）. Therefore, the Qinling Complex is the key to understanding the pre- Paleozoic evolution of the NQOB. The complex, which consists of metagraywackes and marbles, un- derwent regional amphibolite-facies metamorphism. In this study, we constrained the formation age of the Qinling Complex to the period between the late Mesoproterozoic and the early Neoproterozoic （ca. 1062-962 Ma）, rather than the Paleoproterozoic as previously thought. The LA-ICP-MS data show two major metamorphic ages （ca. 499 and ca. 420-400 Ma） for the Qinling Complex. The former age is consistent with the peak metamorphic age of the high- and ultra-high pressure （HP-UHP） rocks in the Qinling Complex, indicating that both the HP-UHP rocks and their country rocks experienced intensive regional metamorphism during the Ordovician. The latter age may constrain the time of partial melting in the NQOB between the late Silurian and early Devonian. The Qinling Complex is mostly affiliated with subduction-accretion processes along an active continental margin, and should contain detritus deposited in a forearc basin.

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.

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.

Base-free oxidative esterification of 5-hydroxymethylfurfural to furan-2,5-dimethylcarboxylate over n-doped carbon-supported Co/Fe bimetallic catalyst under batch-operation or continuous-flow conditions

Developing an efficient and easily available catalyst for the selective conversion of biomass-derived 5-hydroxymethylfurfural(HMF)into furan-2,5-dimethylcarboxylate(FDMC),a valuable biomass-based monomer,remains a high demand but formidable challenge.Herein,a facile strategy for the synthesis of N-doped carbon-supported Co/Fe bimetallic catalyst(CoFe-NC)was developed,which provided an outstanding FDMC yield of 93%in a batch reactor(base-free,80℃,2 bar O_(2),4 h).Interestingly,CoFe-NC also gave a high FDMC yield of 91%under continuous-flow conditions for 80 h(5 bar O_(2),80℃,GHSV 1320 h^(-1),LHSV 0.6 h^(-1),base-free).Notably,it is the first time that a non-noble catalyst gave such a high FDMC yield under continuous-flow conditions.The introduction of Fe could greatly improve both the electron intensity of Co-N_(x)species and basicity of the catalyst,which endowed CoFe-NC with improved O_(2)activation capacity and enhanced dehydrogenation activity for the oxidation-esterification of HMF.This work delineates the efficient strategy on the construction of N-doped carbon-supported non-noble catalyst,which might open a new avenue for developing highly efficient catalyst for FDMC production.

Time-Series Characteristics of Wind Power and Its Impact on Jilin Power Grid

With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation. In order to gain a better grasp of the influence caused by wind power combined to the grid, the paper first establishes the impact characteristic indexes, and then analyzes the regularity of wind power time series in different spatial and temporal scales. At last, according to the analysis results, this paper assesses the impact of time-series characteristics of wind power on power grid, such as the frequency regulation, peak load regulation, which can provide the reference for wind power optimal dispatching of Jilin Power Grid.