Modulation of Electronic States in Bimetallic-doped Nitrogen-Carbon Based Nanoparticles for Enhanced Oxygen Reduction Kinetics

Controlling the local electronic structure of active ingredients to improve the adsorption desorption characteristics of oxygen-containing intermediates over the electrochemical liquid-solid interfaces is a critical challenge in the field of oxygen reduction reaction(ORR)catalysis.Here,we offer a simple approach for modulating the electronic states of metal nanocrystals by bimetal co-doping into carbon-nitrogen substrate,allowing us to modulate the electronic structure of catalytic active centers.To test our strategy,we designed a typical bimetallic nanoparticle catalyst(Fe-Co NP/NC)to flexibly alter the reaction kinetics of ORR.Our results from synchrotron Xray absorption spectroscopy and X-ray photoelectron spectroscopy showed that the co-doping of iron and cobalt could optimize the intrinsic charge distribution of Fe-Co NP/NC catalyst,promoting the oxygen reduction kinetics and ultimately achieving remarkable ORR activity.Consequently,the carefully designed Fe-Co NP/NC exhibits an ultra-high kinetic current density at the operating voltage(71.94 mA/cm^(2)at 0.80 V),and the half-wave potential achieves 0.915 V,which is obviously better than that of the corresponding controls including Fe NP/NC,Co NP/NC.Our findings provide a unique perspective for optimizing the electronic structure of active centers to achieve higher ORR catalytic activity and faster kinetics.

Solid state recycling of Mg-Gd-Y-Zn-Zr alloy chips by isothermal sintering and equal channel angular pressing

The Mg-7Gd-4Y-2Zn-0.5Zr alloy chips were successfully recycled through isothermal sintering and equal channel angular pressing(ECAP).The mechanical properties and microstructure evolution of samples during the recycling process were studied in detail.The eutectic phases in the as-cast alloy transform into long period-stacking ordered(LPSO)phases after homogenization,which can improve the plasticity of the material.After isothermal sintering,the density of the sample is lower than that of the homogenized sample,and oxide films are formed adjacent to the bonding interface of the metal chips.Hence,the plasticity of the sintered sample is poor.Dense samples are fabricated after ECAP.Although the grains are not refined compared to the sintered sample,the microstructure becomes more uniform due to recrystallization.Fiber interdendritic LPSO phase and kinked 14H-LPSO phase are formed in the alloy due to the shear deformation during the ECAP process,which improves the strength and plasticity of the sample significantly.Furthermore,the basal texture is weakened due to the Bc route of the ECAP process,which can increase the Schmid factor of the basal slip system and improve the elongation of the sample.After 2 ECAP passes,the fully densified recycled billet shows superior mechanical properties with an ultimate tensile strength of 307.1 MPa and elongation of 11.1%.

Synthesis of High Purity Lithium Sulfide for Sulfide Solid Electrolyte Applications through Hydrogen Reduction of Lithium Sulfate

This paper is aimed to present a clean,inexpensive and sustainable method to synthesize high purity lithium sulfide(Li_(2)S)powder through hydrogen reduction of lithium sulfate(Li_(2)SO_(4)).A three-step reduction process has been successfully developed to synthesize well-crystallized and single-phase Li_(2)S powder by investigating the melting,sintering and reduction behavior of the mixtures of Li_(2)SO_(4)-Li_(2)S.High purity alumina was found to be the most suitable crucible material for producing high purity Li_(2)S,because it was not attacked by the Li_(2)SO_(4)-Li_(2)S melt during heating,as compared with other materials,such as carbon,mullite,quartz,boron nitride and stainless steel.The use of synthesized LizS resulted in higher purity and substantially higher room temperature ionic conductivity(2.77 mS·cm^(-1))for the argyrodite sulfide electrolyte Li_(6)PS_(5)Cl than commercial Li_(2)S(1.12 mS·cm^(-1)).This novel method offers a great opportunity to produce battery grade Li_(2)S for sulfide solid electrolyte applications.

A review of Al-based material dopants for high-performance solid state lithium metal batteries

As the world transitions to green energy, there is a growing focus among many researchers on the requirement for high-efficient and safe batteries. Solid-state lithium metal batteries(SSLMBs) have emerged as a promising alternative to traditional liquid lithium-ion batteries(LIBs), offering higher energy density, enhanced safety, and longer lifespan. The rise of SSLMBs has brought about a transformation in energy storage, with aluminum(Al)-based material dopants playing a crucial role in advancing the next generation of batteries. The review highlights the significance of Al-based material dopants in SSLMBs applications, particularly its contributions to solid-state electrolytes(SSEs), cathodes, anodes,and other components of SSLMBs. Some studies have also shown that Al-based material dopants effectively enhance SSE ion conductivity, stabilize electrode and SSE interfaces, and suppress lithium dendrite growth, thereby enhancing the electrochemical performance of SSLMBs. Despite the above mentioned progresses, there are still problems and challenges need to be addressed. The review offers a comprehensive insight into the important role of Al in SSLMBs and addresses some of the issues related to its applications, endowing valuable support for the practical implementation of SSLMBs.

DESIGN AND ANALYSIS OF MULTI-STEP AMPLITUDE QUANTIZATION WEIGHTED 2-D SOLID-STATE ACTIVE PHASED ARRAY ANTENNAS

An aperture design technique using multi-step amplitude quantization for two-dimensional solid-state active phased arrays to achieve low sidelobe is described. It can be applied to antennas with arbitrary complex aperture. Also, the gain drop and sidelobe degradation due to random amplitude and phase errors and element (or T/R module) failures are investigated.

新时代背景下焊接专业全英文课程建设与改革实践——以《Solid State Welding》为例

在全球国际化和国家战略“双一流”建设的背景下,积极构建焊接技术与工程专业或焊接方向的国际化人才培养体系与模式,大力推进全英文课程的建设与改革,加快培养焊接领域国际化综合人才具有十分重要的意义。课程建设与改革是新工科建设的实施途径,文中以《Solid State Welding》全英文课程实践为例,不断完善新工科焊接方向课程体系建设,构建与国际接轨的教学内容与方法,将国际化视野、国际化教学思维及方法融入到全英文教育教学中,使学生在掌握国际课程知识的基础上,开拓国际视野,有效培养国际交流与合作能力。

Protein Enrichment of Potato Peels Using Saccharomyces cerevisiae via Solid-State Fermentation Process

In order to add value to potato peels and also curb their environmental pollution problems, this study investigated the protein enrichment of potato peels with Saccharomyces cerevisiae via Solid-State Fermentation (SSF). SSF is a fermentation process which involves solid matrix and is carried out in absence or near absence of free water. SSF of potato peel mashed was carried out with S. cerevisiae at 30°C, pH of 5.5, moisture adjustment between 40 and 90%, addition of ammonium sulphate and urea salts as nitrogen supplements for the microorganisms for 3 days. The results showed that the percentage crude protein content of all the fermented samples increased significantly when compared with the unfermented sample. 40% moisture content adjustment and ammonium sulphate as nitrogen source gave the best result. The crude protein increased from 12.5% to 21.86%, which is 74.88% increment for ammonium sulphate supplementation, and 12.5% to 18.42%, which is 47% increment for urea supplementation. Therefore, the fermented peels could serve as good source of cheap protein enriched feed for livestock.

A critical review on solid-state welding of high entropy alloys-processing,microstructural characteristics and mechanical properties of joints

The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion resistance.These alloys are manufactured by the equal mixing or larger proportions of five or more alloying elements.HEAs exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of mixing.Solid state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA joints.The HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs joints.The similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial applications.Thus,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi alloys.The state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.

Catalytic Performance of Aquathermolysis and Viscosity Reduction of Heavy Oil over a WO_(3)/ZrO_(2) Solid Acid

Tungstated zirconia(WO_(3)/ZrO_(2))solid acid catalysts with different WO_(3) contents were prepared by a hydrothermal method and then used in the catalytic aquathermolysis of heavy oil from Xinjiang.The WO_(3)/ZrO_(2) solid acid catalyst was characterized by a range of characterization methods,including X-ray diffraction,NH3-temperature programmed desorption,and pyridine infrared spectroscopy.The WO_(3) content of the WO_(3)/ZrO_(2) catalysts had an important impact on the structure and property of the catalysts.When the WO_(3) mass fraction was 20%,it facilitated the formation of tetragonal zirconia,thereby enhancing the creation of robust acidic sites.Acidity is considered to have a strong impact on the catalytic performance of the aquathermolysis of heavy oil.When the catalyst containing 20%WO_(3) was used to catalyze the aquathermolysis of heavy oil under conditions of 14.5 MPa,340℃,and 24 h,the viscosity of heavy oil decreased from 47266 to 5398 mPa·s and the viscosity reduction rate reached 88.6%.The physicochemical properties of heavy oil before and after the aquathermolysis were analyzed using a saturates,aromatics,resins,and asphaltenes analysis,gas chromatography,elemental analysis,densimeter etc.After the aquathermolysis,the saturate and aromatic contents significantly increased from 43.3%to 48.35%and 19.47%to 21.88%,respectively,with large reductions in the content of resin and asphaltene from 28.22%to 25.06%and 5.36%to 2.03%,respectively.The sulfur and nitrogen contents,and the density of the oil were significantly decreased.These factors were likely the main reasons for promoting the viscosity reduction of heavy oil during the aquathermolysis over the WO_(3)/ZrO_(2) solid acid catalysts.

Infiltration of Ce0.8Gd0.2O1.9 nanoparticles on Sr2Fe1.5Mo0.5O6-δ cathode for CO2 electroreduction in solid oxide electrolysis cell

Solid oxide electrolysis cell(SOEC) can electrochemically convert CO2 to CO at the gas-solid interface with a high current density and Faradaic efficiency, which has attracted increasing attentions in recent years.Exploring efficient catalyst for electrochemical CO2 reduction reaction(CO2 RR) at the cathode is a grand challenge for the research and development of SOEC. Sr2Fe1.5Mo0.5O6-δ(SFM) is one kind of promising cathode materials for SOEC, but suffers from insufficient activity for CO2 RR. Herein, Gd0.2Ce0.8O1.9(GDC)nanoparticles were infiltrated onto the SFM surface to construct a composite GDC-SFM cathode and improve the CO2 RR performance in SOEC. The current density over the GDC infiltrated SFM cathode with a GDC loading of 12.8 wt% reaches 0.446 A cm-2 at 1.6 V and 800 °C, which is much higher than that over the SFM cathode(0.283 A cm-2). Temperature-programmed desorption of CO2 measurements suggest that the infiltration of GDC nanoparticles significantly increases the density of surface active sites and three phase boundaries(TPBs), which are beneficial for CO2 adsorption and subsequent conversion. Electrochemical impedance spectroscopy results indicate that the polarization resistance of 12.8 wt% GDCSFM cathode was obviously decreased from 0.46 to 0.30 cm^2 after the infiltration of GDC nanoparticles.

Science Letters:Effects of polyurethane matrices on fungal tannase and gallic acid production under solid state culture

The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyurethane matrices were used as the support: continuous, semi-discontinuous and discontinuous. The highest tannase production at 2479.59 U/L during the first 12 h of culture was obtained using the discontinuous matrix. The gallic acid was accumulated at 7.64 g/L at the discontinuous matrix. The results show that the discontinuous matrix of polyurethane is better for tannase production and gallic acid accumulation in a solid state culture bioprocess than the continuous and semi-discontinuous matrices.

Solid State Characterization of Sodium Eritadenate

Knowledge of the solid state is of great importance in the development of a new active pharmaceutical ingredient, since the solid form often dictates the properties and performance of the drug. In the present study, solid state characteristics of the sodium salt of the candidate cholesterol reducing compound eritadenine, 2(R), 3(R))-dihydroxy-4-(9-adenyl)-butanoic acid, were investigated. The compound was crystallized by slow cooling from water and various aqueous ethanol solutions, at different temperatures. Further, the compound solution was subjected to lyophilization and to high vacuum drying. The resulting solids were screened for polymorphism by micro Raman spectroscopy (λex = 830 nm) and the crystallinity was investigated by X-ray powder diffraction. Further, thermal analysis was applied to study possible occurrence of solvates or hydrates. Solids obtained from slow cooling showed crystallinity, whereas rapid cooling gave rise to more amorphous solids. Analysis of difference spectra of the Raman data for solids obtained from slow cooling of solution revealed subtle differences in the structures between crystals derived from pure water and crystals derived from aqueous ethanol solutions. Finally, from the thermal analysis it was deduced that crystals obtained from pure water were stoichiometrically dihydrates whereas crystals obtained from aqueous ethanol solutions were 2.5 hydrates;this formation of different hydrates were supported by the Raman difference analysis.

Latice Deformation and Meso-Phase Structure in Poly(Ethylene Terephthalate)From Solid State Coextrusion

The development of crystalline and Meso-phase structure by solid state extrusion from50℃ to 90℃ is studied for PET. The unit cell parameters of stress-induced crystallites inextrudates are determined as a function of extrusion draw ratio (EDR), and

Solid-State Reaction and Vacancy-Type Defects in Bilayer Fe/Hf Studied by the Slow Positron Beam

The positron annihilation lifetimes and the Doppler broadening by slow positron beam are measured in thin Fe films with thickness 500 nm, a thin Hf film with thickness 100 nm, and the bilayer Fe (50 nm)/Hf (50 nm) on quartz glass substrate. We have analyzed the behavior in vacancy-type defects in each layer through some deposition temperatures and annealing. It is observed that the thin Fe film, the thin Hf film, and the bilayer Fe (50 nm)/Hf (50 nm) already contain many vacancy-type defects. We have investigated the change of densities of the vacancy-carbon complex and the small vacancy-cluster with carbons, through solid-state amorphization of Fe (50 nm)/Hf (50 nm) bilayer.

Optimization of Parameters for the Production of Lipase from Pseudomonas sp. BUP6 by Solid State Fermentation

Solid-state fermentation (SSF) holds tremendous potentials for the production of industrially significant enzymes. The present study describes the production of lipase by a novel rumen bacterium, Pseudomonas sp. strain BUP6 on agro-industrial residues. Pseudomonas sp. strain BUP6 showed higher lipase production when grown in Basal salt medium (BSM) supplemented with oil cakes. Initially, five different oil cakes (obtained after extracting oil from coconut, groundnut, cotton seed, gingelly or soybean) were screened to find out the most suitable substrate-cum-inducer for the production of lipase. Among them, groundnut cake supported the maximum production of lipase (107.44 U/gds). Box-Behnken Design (BBD), followed by response surface methodology (RSM) was employed to optimize the culture parameters for maximizing the production of lipase. Using the software Minitab 14, four different parameters like temperature, pH, moisture content and incubation time were selected for the statistical optimization, which resulted in 0.7 fold increase (i.e., 180.75 U/gds) in production of lipase under the optimum culture conditions (temperature 28&#176C, pH 5.9, moisture 33% and incubation 2 d). Thus, this study signifies the importance of SSF for the production of industrially-significant lipase using agro-industrial residues as solid support.

甜橙皮渣发酵蛋白饲料的研制

利用甜橙加工制汁后的废料--甜橙皮渣进行固态发酵制作蛋白质强化饲料.通过对发酵饲料样品的相关营养成分分析测定等方式筛选菌种、优化发酵条件,即经过单菌试验初步筛选出5株优良菌种,进行3种菌的混合固态发酵,找出适宜该皮渣发酵的优势菌种组合,并对发酵条件进行了优化设计,结果为:添加15%左右的麸皮;在温度29℃左右,pH自然下培养4～5 d;混菌接种比为黑曲霉(2281):康宁木霉(13016):产朊假丝酵母(1807)=1:2:3.该饲料样品的粗蛋白含量比相应对照高出近80%,是纯皮渣对照样粗蛋白(绝干含量)的3～4倍.此强化蛋白饲料未添加任何无机物或有机氮,全天然,无污染.

STUDIES ON THE SOLID STATE REACTIONS OF COORDINATION COMPOUNDS： LXIX STEPWISE REACTION OF CuCl_2．2H_2O WITH 2，2＇－BIPYRIDYL

Consecutive reaction between two solids, CuCl2.2H2O and 2,2'-bipyridyl in 1:2 molar ratio proceed in tWo steps: the salt first converts to the mediate, then the mediate turns to the final product.

Synergistic interactions between the charge‐transport and mechanical properties of the ionic‐liquid‐based solid polymer electrolytes for solid‐state lithium batteries

The performance sensitivity of the solid‐state lithium cells to the synergistic interactions of the charge‐transport and mechanical properties of the electrolyte is well acknowledged in the literature,but the quantitative insights therein are very limited.Here,the charge‐transport and mechanical properties of a polymerized ionic‐liquid‐based solid electrolyte are reported.The transference number and diffusion coefficient of lithium in the concentrated solid electrolyte are measured as a function of concentration and stack pressure.The elastoplastic behavior of the electrolyte is quantified under compression,within a home‐made setup,to substantiate the impact of stack pressure on the stability of the Li/electrolyte interface in the symmetric lithium cells.The results spotlight the interaction between the concentration and thickness of the solid electrolyte and the stack pressure in determining the polarization and stability of the solid‐state lithium batteries during extended cycling.

固相反应制备网状Fe(CO_(0.5)Ni_(0.5))O_5复合氧化物及其电磁学性质研究

在低热固相条件下,采用 FeCl_2·4H_2O,CoCl_2·6H_2O,NiCl_2·6H_2O 与 NH_4HCO_3进行反应,制备出铁钴镍的混合前驱物,在580℃下分解该前驱物。分解产物经 XRD、SEM、TEM、粒度仪表征和化学分析后,获得了具有特殊网状结构,网骨直径约为25nm,网骨长度和直径比例为5的 Fe(Co_(0.5)Ni_(0.5))O_5复合氧化物粉体。时该粉体进行电磁学性质(介电常数ε、磁导率μ和吸波特性γ)测试后发现,其电磁学性质和吸波特性较其它铁氧体粉末改善明显。

Construction of a few-layer g-C_3N_4/α-MoO_3 nanoneedles all-solid-state Z-scheme photocatalytic system for photocatalytic degradation

The suppression of the recombination of electrons and holes(e–h) and the enhancement of the light absorption of semiconductors are two key points toward efficient photocatalytic degradation.Here,we report a few-layer g-C_3N_4/α-MoO_3 nanoneedles(flg-C_3N_4/α-MoO_3 NNs) all-solid-state Z-scheme mechanism photocatalyst synthesized via a typical hydrothermal method in a controlled manner.The recombination of the photo-induced e–h pairs could be effectively restrained by the Z-scheme passageway between the flg-C_3N_4 and α-MoO_3 NNs in the composite,which could also promise a high redox ability to degrade pollutants.And it became possible for the prepared photocatalyst to absorb light in a wide range of wavelengths.The detailed mechanism was studied by electron spin-resonance spectroscopy(ESR).The low-dimensional nanostructure of the two constituents(α-MoO_3 NNs with one-dimensional structure and flg-C_3N_4 with two-dimensional structure) endowed the composite with varieties of excellent physicochemical properties,which facilitated the transfer and diffusion of the photoelectrons and increased the specific surface area and the active sites.The 10 wt% flg-C_3N_4/α-MoO_3 NNs showed the best photocatalytic performance toward RhB degradation,the rate of which was 71.86%,～2.6 times higher than that ofα-MoO_3 NNs.