Precisely Control Relationship between Sulfur Vacancy and H Absorption for Boosting Hydrogen Evolution Reaction

Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy.

Lattice strain induced by trace Pt single atoms in nickel for accelerating industrial hydrogen evolution

Strategically designing the electrocatalytic system and cleverly inducing strain is an effective approach to balance the cost and activity of Pt-based electrocatalysts for industrial-scale hydrogen production.Herein,we present a unipolar pulsed electrodeposition(UPED) strategy to induce strain in the Ni lattice by introducing trace amounts of Pt single atoms(SAs)(0.22 wt%).The overpotential decreased by 183 mV at 10 mA cm^(-2) in 1.0 M KOH after introducing trace amounts of Pt_(SAs).The industrial electrolyzer,assembled with Pt_(SAs)Ni cathode and a commercial NiFeO_(x) anode,requires a cell voltage of 1.90 V to attain 1 A cm^(-2) of current density and remains stable for 280 h,demonstrating significant potential for practical applications.Spherical aberration corrected scanning transmission electron microscopy(AC-STEM),X-ray absorption(XAS),and geometric phase analysis(GPA) indicate that the introduction of trace amounts of Pt SAs induces tensile strain in the Ni lattice,thereby altering the local electronic structure and coordination environment around cubic Ni for enhancing the water decomposition kinetics and fundamentally changing the reaction pathway.The doping-strain strategy showcases conformational relationships that could offer new ideas to construct efficient hydrogen evolution reaction(HER) electrocatalysts for industrial hydrogen production in the future.

应用大分子促进剂的H型水合物储氢特性的分子动力学模拟

纯氢气水合物形成的温压条件极为苛刻(低温高压),限制了其工业应用,而氢气和甲烷混合气水合物形成的温压条件相对温和。通过恒温恒压(NPT)系综分子动力学模拟,研究了环庚酮(C_(7)H_(12)O)、甲基环己烷(C_(6)H_(11)-CH_(3))、1,1-二甲基环己烷(1,1-C_(8)H_(16))和1,2-二甲基环己烷(1,2-C_(8)H_(16))4种大分子促进剂对H型纯氢气水合物以及氢气和甲烷混合气水合物稳定性的影响。结果表明,分别应用4种大分子促进剂的H型水合物牢笼稳定性从大到小依次为1,1-C_(8)H_(16)、1,2-C_(8)H_(16)、C_(6)H_(11)-CH_(3)和C_(7)H_(12)O。相比于纯氢气,氢气和甲烷混合气能够极大缓和热力学条件(温度升高,压力降低)。两种同分异构体(1,1-C_(8)H_(16)和1,2-C_(8)H_(16))作为大分子促进剂,对应的热力学条件表现出较大差异。在纯氢气水合物中,两种同分异构体作为大分子促进剂所需温度条件相近(270 K),而1,1-C_(8)H_(16)作为大分子促进剂所需压力条件(60 MPa)低于1,2-C_(8)H_(16)(100 MPa)。在氢气和甲烷混合气水合物中,1,1-C_(8)H_(16)作为大分子促进剂所需温度条件(270 K)高于1,2-C_(8)H_(16)(260 K),所需压力条件(20 MPa)低于1,2-C_(8)H_(16)(40 MPa)。

H级燃气轮机掺氢发电技术应用现状及关键问题分析

【目的】作为新型电力系统的重要支撑,燃氢燃气轮机有助于降低碳排放,有利于电网调峰,是全球未来战略性新兴产业科技创新领域的焦点。燃气轮机掺氢发电技术从示范走向商业化面临诸多关键问题,亟待解决。【方法】以H级燃气轮机为研究对象,介绍了国内外燃气轮机掺氢发电的战略规划和示范项目,对比了主要燃气轮机厂商H级燃气轮机的技术路线。从氢气来源、系统改造、排放影响以及掺氢发电成本4个方面对未来燃气轮机掺氢发电技术的规模化应用进行分析并提出建议。【结果】可再生能源电解水制氢将是燃气轮机掺氢发电的主要氢气来源;开发适配掺氢不稳定燃烧的新型干式低氮氧化物燃烧器将是未来掺氢燃气轮机系统改造的重点方向;掺氢比例越高,CO_(2)减排量越大,但NOx排放量呈上升趋势,并有超标风险;未来掺氢发电成本可降至天然气发电成本的同等水平。【结论】随着大规模可再生能源制氢成本的降低、碳税的实施以及掺氢发电技术的成熟,燃气轮机掺氢发电将逐步进入规模化应用。

硫化氢在H型高血压中的研究进展

硫化氢(hydrogen sulfide,H_(2)S)是一种参与血管张力调节的内源性气体传递素,具有多种生理特性,如抗高血压、血管松弛、抗炎和抗氧化潜能,在心血管调节中发挥重要作用。同型半胱氨酸(homocysteine,HCY)与心血管疾病的发生、发展密切相关。高同型半胱氨酸血症(HCY≥10μmol·L^(-1))是冠状动脉粥样硬化性心脏病、脑卒中等心脑血管疾病的危险因素,中国学者将伴有高同型半胱氨酸血症的原发性高血压定义为H型高血压,约占我国成年高血压患者的75%。H型高血压的治疗应同时降低血压和血浆HCY的水平。研究表明,H_(2)S能够拮抗高血压和高HCY,提示H_(2)S可能成为H型高血压的潜在治疗靶点。因此,该文就H_(2)S对高血压和HCY的作用机制进行总结。

一种新1H-1,2,3-三唑-4-甲酰胺化合物的合成、晶体结构和氢键研究

合成了一种新的5-甲基-N,1-(二-对甲苯基)-1H-1,2,3-三唑-4-甲酰胺化合物并研究了晶体结构和氢键构成.通过元素分析、核磁共振、质谱、红外光谱对目标化合物进行了表征.化合物的化学式为C_(18)H_(18)N_(4)O,Mr=306.36,晶体属于单斜晶系P21/c空间群中,其晶胞参数为a=1.03251(3)nm,b=0.74042(2)nm,c=2.11902(6)nm,α=90°,β=99.1250(10)(°),γ=90°,V=1.59947(8)nm^(3),Dx=1.272 g5cm^(-3),Z=4.最终R值为0.0429.对目标化合物的芳香体系和氢键体系进行了讨论,并展示了分子晶体在不同平面方向的密堆积.

Effect of hydrogen peroxide concentration on surface properties of Ni-Cr alloys

The effect of concentration of hydrogen peroxide （H2O2） on the surface properties of Ni-Cr alloys was studied. Surface roughness and surface morphology of Ni-Cr alloys were evaluated by surface profiler and scanning electron microscopy after being immersed in different concentrations of H2O2 for 112 h. Surface corrosion products of Ni-Cr alloys were analyzed by photoelectron spectrograph after being immersed in 0% and 30% H2O2. The order of increasing surface roughness of Ni-Cr alloys after being immersed in different concentrations of H2O2 was 0〈3.6%〈10%〈30%. As the concentration of hydrogen peroxide increased, the surface roughness of Ni-Cr alloys increased and the surface morphology showed different degrees of corrosion. According to the XPS results, the corrosion products formed on the outmost surface layer of the studied samples are Ni（OH）2 and BeO.

Effect of Exogenous Hydrogen Sulfide(H_2S) on the Electrocardiogram(ECG) of Rats Generally Anaesthetized by Zoletil

Hydrogen sulfide （H2S） is the third gaseous signaling molecule discovered in recent years, and plays an important physiological role in the cardivascular system. To explore the effects of different doses of exogenous H2S on the electrocardiogram （ECG） of rats generally anesthetized by zoletil, different doses of NariS solution were used for the intervention of intraperitoneal injection 20 rain before the zoletil anesthesia. The ECGs of rats from each treatment group during the time range of 10^th-50^th min were determined under general anesthesia, and then were compared with those from the control group. The results showed that exogenous H2S could significantly reduce the Q-T interval time limit, thus played a role in slowing tachycardia or arrhythmia and other anomalies, thereby protecting the heart. S-T segment and T segment evaluation values were significantly reduced, which might be associated with bradycardia.

2-Ethyl-9,10-anthraquinone assisted sol–gel synthesis of Pd/γ-Al2O3 nanorods with enhanced catalytic performance in 2-ethyl-9,10-anthraquinone hydrogenation

A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully prepared via a facile sol-gel method using aluminum isopropoxide as aluminum precursor and eAQ as structure directing agent,sequential calcination and impregnation process with Na2 PdCl4 solution.The physicochemical properties of the catalysts obtained with different addition amounts of eAQ.were comparatively characterized by XRD,TG-DSC,BET,TEM,CO-TPR,H2-TPR and H2-O2 titration.The results show that addition of eAQ can not only effectively control the textural properties(surface area,pore volume and average pore size) of the catalysts,but also lower their reduction temperature of active metal.Importantly,the catalyst obtained with an addition amount of 4 wt% eAQ shows the highest hydrogenation efficiency of 10.28 g·L^-1,which is 37.3% higher than 7.49 g·L^-1 of the catalyst obtained without eAQ.

Multi-technique integration separation frameworks after steam reforming for coal-based hydrogen generation

Coal-based H2 generation has abruptly increased in recent years.The PSA-VPSA-SC process is the matured and standard framework for H2 purification and CO_(2) capture in many existing plants,including normal and vacuum pressure swing adsorption units in series(PSA-VPSA),and shallow condensation unit(SC).However,this standard process is frequently subjected to low H2 recovery ratio and high purification cost.In this work,H2-selective and C02-selective membrane units,i.e.,HM and CO_(2) M,are attempted to support the standard process and ameliorate constraints.In the beginning,HM unit is arranged after VPSA to enhance H2 recovery from the decarbonized stream,i.e.,the PSA-VPSA-SC/HM process.As a result,H2 recovery ratio can be enhanced significantly from 83%to 98%.In the following,VPSA is replaced with CO_(2) M unit to reduce investment and operation cost,i.e.,the PSA-CO_(2) M-SC/HM process.Accordingly,the specific purification cost is diminished from 33.46 to 32.02 USD·(103 m^(3) H_(2))-1,saved by 4.3%,meanwhile the construction cost is falling back and just a little higher than that for the standard process.In the end,another CO_(2) M unit is launched before PSA,i.e.,the CO_(2) M-PSA-CO_(2) M-SC/HM process,which could unbundle CO_(2) enrichment partially from H2 purification,and then save more investment and operation cost.In comparison with the standard process,this ultimate retrofitted process can be superior in all the three crucial indices,i.e.,recovery ratio,investment,and specific purification cost.On the whole,coal-based H2 generation can be ameliorated significantly through high efficient H2-selective and CO_(2)-selective membrane units.

Study on stability of hydrogenated amorphous silicon films

Hydrogenated amorphous silicon （a-Si：H） films with high and same order of magnitude photosensitivity （-10^5） but different stability were prepared by using microwave electron cyclotron resonance chemical vapour deposition system under the different deposition conditions. It was proposed that there was no direct correlation between the photosensitivity and the hydrogen content （CH） as well as H-Si bonding configurations, but for the stability, they were the critical factors. The experimental results indicated that higher substrate temperature, hydrogen dilution ratio and lower deposition rate played an important role in improving the microstructure of a-Si：H films. We used hydrogen elimination model to explain our experimental results.

Renewable hydrogen production from steam reforming of glycerol(SRG)over ceria-modified Y-alumina supported Ni catalyst

Excess crude glycerol derived as a by-product from biodiesel industry prompts the need to valorise glycerol to value-added chemicals.In this context,catalytic steam reforming of glycerol(SRG) was proposed as a promising and sustainable alternative for producing renewable hydrogen(H2).Herein,the development of nickel(Ni) supported on ceria-modified mesoporous γ-alumina(γ-Al2 O3) catalysts and their applications in catalytic SRG(at550-750℃ atmospheric pressure and weight hourly space velocity,WHSV,of 44,122 ml·g^-1·h^-1(STP)) is presented.Properties of the developed catalysts were characterised using many technique s.The findings show that ceria modification improved Ni dispersion on γ-Al2 O3 catalyst support with highly active small Ni particles,which led to a remarkable catalytic performance with the total glycerol conversion(ca.99%),glycerol conversion into gaseous products(ca.77%) and H2 yield(ca.62%).The formation rate for H2 production(14.4 ×10^(-5)mol·s^-1·g^-1, TOF(H2)=3412 s^-1) was significantly improved with the Ni@12 Ce-Al2 O3 catalyst,representing nearly a 2-fold increase compared with that of the conventional Ni@AI2 O3 catalyst.In addition,the developed catalyst also exhibited comparatively high stability(for 12 h) and coke resistance ability.

Effect of H_2S on the transformation of 1-hexene over NiMoS/γ-Al_2O_3 with hydrogen

The effect of H2S contents on the transformation of 1-hexene with hydrogen over NiMoS/γ-Al2O3 catalyst was investigated.Inhibition of H2S on both hydrogenation and isomerization reactions of olefin has been demonstrated.And the promotion effect of H2S on the formation of C6 thiols and C12 thioethers has also been observed.It was found out that there was only one type of active site on the NiMoS/γ-Al2O3 for reactions which include hydrogenation reaction,isomerization reaction and sulfides formation reaction,and the formation reactions of sulfides were superior to both hydrogenation and isomerization reactions.The reaction network for the conversion of 1-hexene in the presence of H2S was proposed.

Differential generation of hydrogen peroxide upon exposure to zinc and cadmium in the hyperaccumulating plant specie(Sedum alfredii Hance)

Sedum alfredii Hance has been identified as zinc(Zn) and cadmium(Cd) co-hyperaccumulator.In this paper the relationships of Zn or Cd hyperaccumulation to the generation and the role of H2O2 in Sedum alfredii H.were examined.The results show that Zn and Cd contents in the shoots of Sedum alfredii H.treated with 1000 μmol/L Zn2+ and/or 200 μmol/L Cd2+ increased linearly within 15 d.Contents of total S,glutathione(GSH) and H2O2 in shoots also increased within 15 d,and then decreased.Total S and GSH contents in shoots were higher under Cd2+ treatment than under Zn2+ treatment.However,reverse trends of H2O2 content in shoots were obtained,in which much higher H2O2 content was observed in Zn2+-treated shoots than in Cd2+-treated shoots.Similarly,the microscopic imaging of H2O2 accumulation in leaves using H2O2 probe technique showed that much higher H2O2 accumulation was observed in the Zn2+-treated leaf than in the Cd2+-treated one.These results suggest that there are different responses in the generation of H2O2 upon exposure to Zn2+ and Cd2+ for the hyperaccumulator Sedum alfredii H.And this is the first report that the generation of H2O2 may play an important role in Zn hyperaccumulation in the leaves.Our results also imply that GSH may play an important role in the detoxification of dissociated Zn/Cd and the generation of H2O2.

CO_(2) hydrogenation selectivity shift over In‐Co binary oxides catalysts:Catalytic mechanism and structure‐property relationship

The hydrogenation of CO_(2) into methanol has attracted much attention and In_(2)O_(3) is a promising catalyst.Introducing metal elements into In_(2)O_(3)(M/In_(2)O_(3))is one of the main strategies to improve its performance.However,its mechanism and active sites remain unclear and need to be further elucidated.Here,the noble‐metal‐free In_(x)‐Co_(y) oxides catalysts were prepared.Much‐improved performance and obvious product selectivity shift were observed.The optimized catalyst(In_(1)‐Co_(4))(9.7 mmol g_(cat)^(–1) h^(–1))showed five times methanol yields than pure In_(2)O_(3)(2.2 mmol g_(cat)^(–1) h^(–1))(P=4.0 MPa,T=300°C,GHSV=24000 cm^(3)_(STP) g_(cat)^(–1) h^(–1),H_(2):CO_(2)=3).And the cobalt‐catalyzed CO_(2) methanation activity was suppressed,although cobalt was most of the metal element.To unravel this selectivity shift,detailed catalysts performance evaluation,together with several in‐situ and ex‐situ characterizations,were employed on cobalt and In‐Co for comparative study.The results indicated CO_(2) hydrogenation on cobalt and In‐Co catalyst both followed the formate pathway,and In‐Co reconstructed and generated a surface In_(2)O_(3)‐enriched core‐shell‐like structure under a reductive atmosphere.The enriched In_(2)O_(3) at the surface significantly enhanced CO_(2) adsorption capacity and well stabilized the intermediates of CO_(2) hydrogenation.CO_(2) and carbon‐containing intermediates adsorbed much stronger on In‐Co than cobalt led to a feasible surface C/H ratio,thus allowing the*CH_(3)O to desorb to produce CH_(3)OH instead of being over‐hydrogenated to CH_(4).

Research on the optimum hydrogenated silicon thin films for application in solar cells

Hydrogenated silicon （Si：H） thin films for application in solar ceils were deposited by using very high frequency plasma enhanced chemical vapour deposition （VHF PECVD） at a substrate temperature of about 170 ℃, The electrical, structural, and optical properties of the films were investigated. The deposited films were then applied as i-layers for p-i-n single junction solar cells. The current-voltage （I - V） characteristics of the cells were measured before and after the light soaking. The results suggest that the films deposited near the transition region have an optimum properties for application in solar cells. The cell with an i-layer prepared near the transition region shows the best stable performance.

Theoretical Studies on the Stabilities and Hydrogen Bond Actions of (H_2O)_n Clusters

The stable configurations and hydrogen bond nature of （H2O）n clusters （n = 3-6） have been investigated by the B3LYP method at the 6-31＋＋g^＊＊ level. Upon calculation, four conclusions have been drawn： （1） In the （H2O）3-5 clusters, cyclic configurations were confirmed to be the most stable. But in the （H2O）3-4 ones, only cyclic configurations could be observed. From n = 5 （（H2O）5 clusters）, three-dimensional configuration could be found： （2） In the （H2O）6 clusters, all configurations are inclined to be three-dimensional except the most stable configuration which is cyclic; （3） The stable order of （H2O）6 clusters indicates that it is the arrangement of hydrogen bond that plays a decisive role in the cluster stabilities, the zero-point energy is also important, and cluster stabilities are independent on the number of hydrogen bonds; （4） There exist strong cooperativity and superadditivity in the （H2O）n clusters.

Corrosion Rate of Hydrogenation to C110 Casing in High H_2S Environment

The corrosion behavior of C110 bushing at high temperature and high pressure with a high H2S / CO2 was studied, and a basis for the materials selection of sour gas well bushing was provided in H2S, CO2 and saline coexisting environment. Under acidic condiction, hydrogen atoms greatly entered into the material and caused the material properties changed. Weight loss method was used to study the corrosion rate of hydrogen charging samples and original untreated samples in simulated oil field environment. PAR2273 electrochemical workstation was used to examine the electrochemical performance of samples untreated, hydrogen charging after reacting in autoclave. The corrosion product film was observed through SEM. The experimental results show that sample with hydrogen charging has a much more obvious partial corrosion and pitting corrosion than the untreated blank sample even the downhole corrosion speed of bushing is increased after being used for a period of time. Polarization curve shows the corrosion tendency is the same between sample with or without hydrogen charging and corrosion tendency is reduced by corrosion product film. A layer of dense product film formed on the surface of samples provides a certain protective effect to the matrix, but cracked holes which will accelerate partial corrosion of the sample were also observed.

Effects of Roudoukou-8 San Extract on Hydrogen Peroxide Induced Cardiomyocyte Injury

[Objectives] To study the effects of Roudoukou-8 San extract on hydrogen peroxide( H_2O_2) induced cardiomyocyte injury of rats and explore its action mechanism. [Methods] The cardiomyocytes of neonatal rats were isolated and cultured,and the H_2O_2 induced cardiomyocyte injury model was established. Methyl thiazolyl tetrazolium( MTT) assay was used to detect the protective effects of Roudoukou-8 San extract on H_2O_2 induced cardiomyocyte. The effects of Roudoukou-8 San on cardiomyocyte morphology were observed under inverted microscope. The contents of lactate dehydrogenase( LDH),creatine kinase( CK) and aspartate aminotransferase( AST) in cell culture medium were determined by automatic biochemical instrument; the levels of malondialdehyde( MDA),superoxide dismutase( SOD) and nitric oxide( NO) in the cells were detected by kit method. The apoptotic morphology of cardiomyocytes was observed by Hoechst fluorescence staining.Cell apoptosis were measured by Annexin V and PI double staining and flow cytometer. [Results]100 μmol/L of H_2O_2 acting 2 h could cause about 50% of cardiomyocyte injury. H_2O_2 model group showed increased cell gap,decreased cell count,cell cytoplasmic vacuoles and other obvious damages. Compared with H_2O_2 model group,in Roudoukou-8 San extract dose groups,cardiomyocyte morphology showed different degrees of improvement,Roudoukou-8 San extract can significantly reduce the content of LDH,CK and AST in H_2O_2 injured myocardial cell culture solution,significantly reduce content of MDA and NO in H_2O_2 injured myocardial cells,increase the SOD activity,and significantly inhibit the apoptosis of H_2O_2 injured myocardial cells. [Conclusions]Through improving the cell survival status,increasing the cell viability,reducing oxidative stress injury,inhibiting inflammatory responses,and inhibiting apoptosis,Roudoukou-8 San extract can improve the state of H_2O_2 induced cardiomyocyte injury,so as to protect H_2O_2 injured myocardial cells.

INVESTIGATION OF HYDROGEN INDUCED DUCTILE BRITTLE TRANSITION IN 7175 ALUMINUM ALLOY

Effects of hydrogen on the mechanical properties of differently aged 7175 aluminum alloys were investigated by using cathodic H-permeation, slow strain rate tension and so on. The results indicate that both the yield stress and the percentage reduction of area decrease with increasing hydrogen charging time, and the degree of reduction decreases as aging time increases for the same hydrogen charging time.