过渡金属氮化物的活性起源、合成方法及电催化应用

过渡金属电催化剂因其优良的电催化性能、低廉的成本,以及在电解水、燃料电池、锌空电池等领域展现出极大的应用潜力,逐渐成为人们的研究热点。其中,过渡金属氮化物(Transition Metal Nitrides,TMNs)因氮化过程能使金属的d带收缩变窄,填充态发生改变,从而调节金属-氢的键能,达到提高导电性及催化活性的目的,近来备受学者们的关注。因此,本文综述了TMNs纳米电催化剂的最新研究进展,包括借助d带理论讨论了氮元素对其结构及活性的影响;评述了TMNs的物理、化学等合成方法及掺杂、复合等改性方法;列举了其在析氢反应、析氧反应、氧还原反应等电催化领域中的重要应用;最后,指出了TMNs在现阶段所面临的挑战和问题,并对其今后发展作出展望。

Reproductive traits associated with invasiveness in Conyza sumatrensis

Conyza sumatrensis （Retz.） E. Walker, a member of Asteraceae, is a highly invasive species. However, its reproduction biology remains poorly known. To understand the role of reproductive traits in successful invasion of the species, we studied several traits of its reproductive system： the miniature capitulum and gynomonoecious sexual system, the biology and phenology of capitula and florets, pollen/ovule ratio, the mating system （selfcompatibility）, flower visitors, physical traits and dispersal potential of achenes, germination potential of achenes from manually pollinated capitula, and the association of these traits with invasiveness. Our study showed that the reproductive traits of autonomous seed production, versatile mating system of self- and cross-pollination, and generalized pollination system might contribute to the species＇ successful invasive capability. The invasiveness was further enhanced by the high and rapid production of achenes, as well as the high percentage, rapid germination rate and high dispersal capability of achenes. It was concluded that in annual or winter-annual weeds, autonomous seed production contributed significantly to the invasiveness of the species.

Prognosis in prolonged coma patients with diffuse axonal injury assessed by somatosensory evoked potential

A total of 43 prolonged coma patients with diffuse axonal injury received the somatosensory evoked potential examination one month after injury in the First Affiliated Hospital, School of Medicine, Zhejiang University in China. Somatosensory evoked potentials were graded as normal, abnormal or absent （grades I-III） according to N20 amplitude and central conduction time. The outcome in patients with grade III somatosensory evoked potential was in each case unfavorable. The prognostic accuracy of grade III somatosensory evoked potential for unfavorable and non-awakening outcome was 100% and 80%, respectively. The prognostic accuracy of grade I somatosensory evoked potential for favorable and wakening outcome was 86% and 100%, respectively. These results suggest that somatosensory evoked potential grade is closely correlated with coma severity and degree of recovery. Somatosensory evoked potential is a valuable diagnostic tool to assess prognosis in prolonged coma patients with diffuse axonal injury.

通滞活络颗粒冲剂联合复方樟柳碱治疗中老年后天性眼肌麻痹

目的:研究通滞活络颗粒冲剂联合复方樟柳碱对中老年后天性眼肌麻痹的临床治疗效果。方法:选择2015-01/2017-10在我院进行诊治的81例81眼中老年后天性眼肌麻痹患者,按治疗方式的不同分为观察组40例40眼和对照组41例41眼。对照组在患侧颞浅动脉旁给予皮下注射复方樟柳碱2mL,观察组在对照组的治疗基础上联合服用通滞活络颗粒冲剂。比较两组的临床治疗效果、复视像距离及治疗前后基底动脉收缩期的搏动指数以及血流速度。结果:观察组中老年后天性眼肌麻痹患者的有效率为92%(37/40),明显高于对照组的73%(30/41,P<0.05);观察组治愈时间≤2wk的发生率明显高于对照组(P<0.05);两组治疗后的复视像距离均明显缩短(P<0.01),且观察组复视像距离明显短于对照组(P<0.01);两组治疗后的搏动指数均明显降低(P<0.01),血流速度均明显升高(P<0.01),且观察组更为明显(P<0.01)。结论:通滞活络颗粒冲剂联合复方樟柳碱对中老年后天性眼肌麻痹的临床治疗效果明显优于单纯皮下注射复方樟柳碱,可有效改善椎-基底动脉的血流状况,具有较高的临床应用价值。

Synthesis of novel thionocarbamate for copper-sulfur flotation separation and its adsorption mechanism

As a novel collector, O-isopropyl-N,N-diethyl thionocarbamate(IPDTC) was designed and synthesized for copper-sulfur flotation separation. Density functional theory calculations were performed to investigate the electronic structures of IPDTC. The results showed that IPDTC had higher energy of the highest occupied molecular orbital but lower electronegativity than O-isopropyl-N-ethyl thionocarbamate(Z-200). It was predicted that IPDTC had strong collection ability according to the reaction energy criteria. Flotation results demonstrated that the collecting ability of IPDTC to chalcopyrite and pyrite was stronger than that of Z-200. Then, the flotation mechanism was analyzed by measurements of surface tension, adsorption capacity, XPS, FTIR and zeta potential. These results indicated that IPDTC could reduce the solution surface tension. The adsorption capacity of IPDTC on chalcopyrite was higher than that on pyrite, consistent with the results of the flotation tests. FTIR, zeta potential and XPS results also demonstrated that IPDTC was strongly absorbed on the chalcopyrite surface by formation of Cu—S—C bonds, but showed a weak affinity on the pyrite surface.

Separation of tungsten and molybdenum with solvent extraction using functionalized ionic liquid tricaprylmethylammonium bis(2,4,4-trimethylpentyl)phosphinate

Functionalized ionic liquids(FILs)as extractants were employed for the separation of tungsten and molybdenum from a sulfate solution for the first time.The effects of initial pH,extractant concentration,metal concentrations in the feed were comprehensively investigated.The results showed that tricaprylmethylammonium bis(2,4,4-trimethylpentyl)phosphinate([A336][Cyanex272])could selectively extract W over Mo at an initial pH value of 5.5;the best separation factorβ_(W/Mo) of 25.61 was obtained for a solution with low metal concentrations(WO3:2.49 g/L,Mo:1.04 g/L).The[A336][Cyanex272]system performed effectively for solutions of different W/Mo molar ratios and different metal ion concentrations in the feed.The chemical reaction between[A336][Cyanex272]and W followed the ion association mechanism,which was further proved by the Fourier-transform infrared(FTIR)spectra of loaded[A336][Cyanex272]and the free extractant.The stripping experiments indicated that 95.48%W and 100.00%Mo were stripped using a 0.20 mol/L sodium hydroxide solution.Finally,the selective extractions of W and Mo from two synthetic solutions of different high metal concentrations were obtained;the separation factorβW/Mo reached 23.24 and 17.59 for the first and second solutions,respectively.The results suggest the feasibility of[A336][Cyanex272]as an extractant for the separation of tungsten and molybdenum.

In situ TiB2/Cu composites fabricated by spray deposition using solid-liquid and liquid-liquid reactions

In situ TiB2/Cu composites were fabricated by both solid-liquid(S-L)and liquid-liquid(L-L)reactive spray deposition in combination with cold rolling and annealing.The microstructure and properties of the fabricated TiB2/Cu composites were investigated.The results show that the reactive mode and rolling treatment are the main factors affecting the microstructure and properties of the TiB2/Cu composite.The in situ reaction in the L-L reaction can be carried out more completely.By controlling the rolling and annealing process,the relative density and the properties of the as-deposited composites are optimized.The comprehensive performance of the deformed TiB2/Cu composite prepared by L-L reactive spray deposition(401 MPa and 83.5%IACS)is better than that by S-L reactive spray deposition(520 MPa and 20.2%IACS).

Improved 4H-SiC UMOSFET with super-junction shield region

This article investigates an improved 4H-SiC trench gate metal–oxide–semiconductor field-effect transistor(MOSFET)(UMOSFET)fitted with a super-junction(SJ)shielded region.The modified structure is composed of two n-type conductive pillars,three p-type conductive pillars,an oxide trench under the gate,and a light n-type current spreading layer(NCSL)under the p-body.The n-type conductive pillars and the light n-type current spreading layer provide two paths to and promote the diffusion of a transverse current in the epitaxial layer,thus improving the specific on-resistance(R_(on,sp)).There are three p-type pillars in the modified structure,with the p-type pillars on both sides playing the same role.The p-type conductive pillars relieve the electric field(E-field)in the corner of the trench bottom.Two-dimensional simulation(silvaco TCAD)indicates that Ron,sp of the modified structure,and breakdown voltage(V_(BR))are improved by 22.2%and 21.1%respectively,while the maximum figure of merit(FOM=V_(BR)^(2)/R_(on,sp)) is improved by 79.0%.Furthermore,the improved structure achieves a light smaller low gate-to-drain charge(Q_(gd))and when compared with the conventional UMOSFET(conventional-UMOS),it displays great advantages for reducing the switching energy loss.These advantages are due to the fact that the p-type conductive pillars and n-type conductive pillars configured under the gate provide a substantial charge balance,which also enables the charge carriers to be extracted quickly.In the end,under the condition of the same total charge quantity,the simulation comparison of gate charge and OFF-state characteristics between Gaussdoped structure and uniform-doped structure shows that Gauss-doped structure increases the V_(BR)of the device without degradation of dynamic performance.

A 4H-SiC trench MOSFET structure with wrap N-type pillar for low oxide field and enhanced switching performance

An optimized silicon carbide(SiC)trench metal-oxide-semiconductor field-effect transistor(MOSFET)structure with side-wall p-type pillar(p-pillar)and wrap n-type pillar(n-pillar)in the n-drain was investigated by utilizing Silvaco TCAD simulations.The optimized structure mainly includes a p+buried region,a light n-type current spreading layer(CSL),a p-type pillar region,and a wrapping n-type pillar region at the right and bottom of the p-pillar.The improved structure is named as SNPPT-MOS.The side-wall p-pillar region could better relieve the high electric field around the p+shielding region and the gate oxide in the off-state mode.The wrapping n-pillar region and CSL can also effectively reduce the specific on-resistance(Ron,sp).As a result,the SNPPT-MOS structure exhibits that the figure of merit(Fo M)related to the breakdown voltage(V_(BR))and Ron,sp(V_(BR)^2R_(on,sp))of the SNPPT-MOS is improved by 44.5%,in comparison to that of the conventional trench gate SJ MOSFET(full-SJ-MOS).In addition,the SNPPT-MOS structure achieves a much fasterwitching speed than the full-SJ-MOS,and the result indicates an appreciable reduction in the switching energy loss.

Competitive precipitation behavior of hybrid reinforcements in copper matrix composites fabricated by powder metallurgy

Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers(TiB_(w))and titanium diboride particles(TiB_(2p))were fabricated by powder metallurgy.Microstructural observations showed competitive precipitation behavior between TiB_(w) and TiB_(2p),where the relative contents of the two reinforcements varied with sintering temperature.Based on thermodynamic and kinetic assessments,the precipitation mechanisms of the hybrid reinforcements were discussed,and the formation of both TiB_(w) and TiB_(2p) from the local melting zone was thermodynamically favored.The precipitation kinetics were mainly controlled by a solid-state diffusion of B atoms.By forming a compact compound layer,in situ reactions were divided into two stages,where Zener growth and Dybkov growth prevailed,respectively.Accordingly,the competitive precipitation behavior was attributed to the transition of the growth model during the reaction process.

Neuroprotective effect of Cerebralcare Granule after cerebral ischemia/reperfusion injury

Cerebralcare Granule（CG） improves cerebral microcirculation and relieves vasospasm,but studies investigating its therapeutic effect on cerebral ischemia/reperfusion injury are lacking.In the present study,we administered CG（0.3,0.1 and 0.03 g/m L intragastrically） to rats for 7 consecutive days.We then performed transient occlusion of the middle cerebral artery,followed by reperfusion,and administered CG daily for a further 3 or 7 days.Compared with no treatment,high-dose CG markedly improved neurological function assessed using the Bederson and Garcia scales.At 3 days,animals in the high-dose CG group had smaller infarct volumes,greater interleukin-10 expression,and fewer interleukin-1β-immunoreactive cells than those in the untreated model group.Furthermore,at 7 days,high-dose CG-treated rats had more vascular endothelial growth factor-immunoreactive cells,elevated angiopoietin-1 and vascular endothelial growth factor expression,and improved blood coagulation and flow indices compared with untreated model animals.These results suggest that CG exerts specific neuroprotective effects against cerebral ischemia/reperfusion injury.

Validation of the eighth edition of the AJCC staging system for patients with pancreatic adenocarcinoma initially receiving chemoradiotherapy and proposal of modifications

Objective:To validate the eighth edition of the AJCC staging system in patients with pancreatic adenocarcinoma receiving only stereotactic body radiation therapy and chemotherapy,and to propose modifications to improve prognostic accuracy.Methods:Patients with pathologically confirmed pancreatic adenocarcinoma without metastasis who were undergoing only chemoradiotherapy were included and staged according to the seventh and eighth editions of the AJCC staging system.Meanwhile,another group of stage T4 patients from the above enrollment with only portal vein involvement with or without tumor thrombi(PV±PVTT)were retrieved for survival comparisons.Modifications were proposed according to the survival comparisons.A cohort from the SEER database was used for external validation of the modified staging system.Results:A total of 683 patients were included.Patients with N2 or N1 but different T stages had significantly different survival outcomes according to the eighth edition.The survival of patients with(PV±PVTT)was comparable to that of patients with T4 tumors.The concordance index of the seventh and eighth editions,and the modified staging system was 0.744(95%CI:0.718—0.769),0.750(95%CI:0.725—0.775),and 0.788(95%CI:0.762-0.813),respectively.For external validation,the concordance index was 0.744(95%CI:0.718-0.770),0.750(95%CI:0.724-0.776),and 0.788(95%CI:0.762-0.814),respectively.Conclusions:The modified staging system is suggested to have the m ost accurate prognostic value.Hence,PV土PVTT should be added to the definition of T4 tumors regardless of tumor size.Patients with N2 or N1 in different T stages could be regrouped into different substages.Additionally,stage III should be subclassified into IIIA(T3N 2 and T4N 0)and IIIB(T4N 1-2).

“电磁场与微波技术”军队网络课程的设计与实现

随着军队信息技术和网络技术的飞速发展,军队网络课程的建设与应用已经越来越受到军队院校的重视。本文阐述了基于军队院校网络教学应用系统的“电磁场与微波技术”网络课程的建设,主要包括:设计原则、教学内容、考试、课程素材资源建设,并详细介绍了该网络课程的功能,为相关网络课程建设提供参考。

Expression of metabotropic glutamate receptor 1a in a rat cortical neuronal model of in vitro mechanical injury and the effects of its competitive antagonist (RS)-1-aminoindan-1,5-dicarboxylic acid

The present study established a rat cortical neuronal model of in vitro mechanical injury. At 30 minutes after injury, the survival rate of the injured cortical neurons was decreased compared with normal neurons, and was gradually decreased with aggravated degree of injury. Reverse transcription-polymerase chain reaction results showed that at 1 hour after injury, there was increased expression of metabotropic glutamate receptor la in cortical neurons. Immunohistochemical staining results showed that at 30 minutes after injury, the number of metabotropic glutamate receptor 1a-positive cells increased compared with normal neurons. At 12 hours after injury, lactate dehydrogenase activity in the （RS）-l-aminoindan-1, 5-dicarboxylic acid （AIDA）-treated injury neurons was si[jnificantly decreased than that in the pure injury group. At 1 hour after injury, intracellular free Ca＂＋ concentration was markedly decreased in the AIDA-treated injury neurons than that in the pure injury neurons. These findings suggest that after mechanical injury to cortical neurons, metabotropic glutamate receptor la expression increased. The resulting increase in intracellular free Ca2＋ concentration was blocked by AIDA, indicating that AIDA exhibits neuroprotective effects after mechanical injury.

Accuracy of a Simple Digital Templating in Primary Uncemented Total Hip Arthroplasty

Objective To introduce a simple preoperative digital templating in uncemented total hip arthroplasty(THA) and to determine its accuracy for preoperative size selection of the prostheses.Methods A prospective study of digital planned THAs was performed on 90 hips with different types of prostheses from August 2013 to Angust 2014.The plastic templates of different types of prostheses were scanned for desired digital templating and the scanned images were then processed to the transparent,digital templates using Photoshop software.We calibrated the scales of the digital templates with the preoperative radiographs,and then selected the right size of the component.The preoperatively digital planned component sizes were compared to the actual sizes used in the operation,as well as the preoperatively traditional planned sizes.Results In either cup or stem templating,no difference was found among the groups with different types of prostheses,and the accuracy of digital templating was statistically higher than traditional templating.In cup templating,digital planned and implanted cup sizes were identical in 43.33% of the cases,78.89% of the cup sizes were predicted within 1 size(± 2mm) and 95.56% were predicted within 2 sizes(±4 mm),all significantly higher than the results of traditional planned sizes(30.00%,P=0.044;61.11%,P=0.007;82.22%,P=0.004).The exact femoral stem size was predicted in 40.00% of cases using the digital templating,84.44% of stem sizes were predicted within 1 size,and 93.33% within 2 sizes,better than using traditional templating(25.56%,P=0.028;53.33%,P<0.001;77.77%,P=0.003).Conclusion This simple digital preoperative templating is an accurate and reproducible process to preoperatively predict the implant size of uncemented THA.

Altered expression of metabotropic glutamate receptor 1 alpha after acute diffuse brain injury Effect of the competitive antagonist 1-aminoindan-1, 5-dicarboxylic acid

The diffuse brain injury model was conducted in Sprague-Dawley rats, according to Marmarou＇s free-fall attack. The water content in brain tissue, expression of metabotropic glutamate receptor la mRNA and protein were significantly increased after injury, reached a peak at 24 hours, and then gradually decreased. After treatment with the competitive antagonist of metabotropic glutamate receptor la, （RS）-l-aminoindan-1,5-dicarboxylic acid, the water content of brain tissues decreased between 12-72 hours after injury, and neurological behaviors improved at 2 weeks. These experimental findings suggest that the 1-aminoindan-1, 5-dicarboxylic acid may result in marked neuroprotection against diffuse brain injury.

Setosphlides A-D, New Isocoumarin Derivatives from the Entomogenous Fungus Setosphaeria rostrate LGWB-10

Investigation of the entomogenous fungus Setosphaeria rostrate LGWB-10 from Harmonia axyridis led to the isolation of four new isocoumarin derivatives,setosphlides A-D(1-4),and four known analogues(5-8).Their planar structures and the relative configurations were elucidated by comprehensive spectroscopic methods.The absolute configurations of isocoumarin nucleus for 1-4 were elucidated by their ECD spectra.The C-10 relative configurations for the pair of C-10 epimers(1 and 2)were established by comparing the magnitude of the computed 13C NMR chemical shifts(Δδcalcd.)with the experimental 13C NMR values(Δδexp.)for the epimers.All of the isolated compounds(1-8)were evaluated for their cytotoxicities against four human tumor cell lines MCF-7,MGC-803,HeLa,and Huh-7.

Analysis of Local Features and Shaping of Rural Tourism in Kuandian of Liaoning Province

In the process of rural tourism development and planning,local features and related concepts have attracted more and more attention from scholars with the deepening of development. As one form of places,rural areas have extraordinary significance,so the participation of local residents,the integration of traditional culture and the inheritance of local features should be fully taken into account in the development of rural tourism. However,some local governments refuse to focus on local features in the process of rural tourism planning,so the planning and development of rural tourism in many places are similar and can't reflect the unique features of local culture. Therefore,this paper takes Kuandian Manchu Autonomous County in Liaoning Province as an example,which has rich rural tourism resources and unique features,and conducts research on the tourism planning with local features from local perspective.

Enantioselective Construction of Polycyclic Chromanes through Organocatalytic Sequential Quintuple Reaction via One-Pot Step-Wise Procedure

An efficient and highly stereoselective synthetic method to access polycyclic chromanes has been achieved through organocatalyzed one-pot step-wise reactions involving 2-hydroxycinnamaldehydes,2-aminochalcones,and malononitrile as substrates.The reactions underwent a quintuple process by aza-Michael/Michael/Knoevenagel/oxa-Michael/aldol-type reaction in sequence to give products bearing 3 new generated rings and 5 chiral centers in moderate to quantitative yields with excellent stereoselectivities.

Comprehensive evaluation of an ionic liquid based deep purification process for NH_(3)-containing industrial gas

Ammonia(NH_(3))emission has caused serious environment issues and aroused worldwide concern.The emerging ionic liquid(IL)provides a greener way to efficiently capture NH_(3).This paper provides rigorous process simulation,optimization and assessment for a novel NH_(3)deep purification process using IL.The process was designed and investigated by simulation and optimization using ionic liquid[C_(4)im][NTF_(2)]as absorbent.Three objective functions,total purification cost(TPC),total process CO_(2)emission(TPCOE)and thermal efficiency(ηeff)were employed to optimize the absorption process.Process simulation and optimization results indicate that at same purification standard and recovery rate,the novel process can achieve lower cost and CO_(2)emission compared to benchmark process.After process optimization,the optimal functions can achieve 0.02726$/Nm~3(TPC),311.27 kg CO_(2)/hr(TP-COE),and 52.21%(ηeff)for enhanced process.Moreover,compared with conventional process,novel process could decrease over$3 million of purification cost and 10000 tons of CO_(2)emission during the life cycle.The results provide a novel strategy and guidance for deep purification of NH_(3)capture.