Microstructure and ferromagnetism of heavily Mn doped SiGe thin flims

Heavily Mn-doped SiGe thin films were grown by radio frequency magnetron sputtering and then treated by postgrowth thermal annealing.Structural characterizations reveal the coexistence of Mn-diluted SiGe crystals and Mn-rich nanoclusters in the annealed films.Magnetic measurements indicate the ferromagnetic ordering of the annealed samples above room temperature.The data suggest that the ferromagnetism is probably mainly contributed by the Ge-rich nanoclusters and partially contributed by the tensile-strained Mn-diluted SiGe crystals.The results may be useful for room temperature spintronic applications based on group IV semiconductors.

The effect of thermal fluid derived from mud diapir on sandstone reservoirs in the Yinggehai Basin, South China Sea

The underground thermal fluid is one of the significant factors controlling the formation and quality of reservoirs.The Huangliu Formation(N_(1)h)in YF1 area of the central depression belt in the Yinggehai Basin,South China Sea,is characterized by intense thermal fluid activities related to mud diapir and large-scale shallow-water gravity flow deposits.The multi-episodic invasion of high-temperature and CO_(2)-rich thermal fluid into the formation induces complex water-rock reaction during diagenetic pro-cess,providing a preferable investigation opportunity for revealing how thermal fluid affects reservoir quality.This study characterizes the reservoirs in the formation through core and thin section analyses as well as physical property test.The reservoirs are dominated by fine-grained sandstone characterized by medium porosity(15.2-21.3%)and lower permeability(0.56-15.75mD).Based on an analysis of casting thin section,cathode luminescence(CL),scanning electron microscope(SEM),carbon and oxygen isotope,inclusion test,and electron-probe microanalysis(EPMA),we systematically investigate the diagenetic patterns and pore evolution process for the reservoirs in the formation.The episodic invasion of thermal fluid occurred approximately 0.4 Ma ago plays an important role in controlling reservoir development:The CO_(2)-rich formation water induces massive late-stage dissolution,resulting in a higher proportion of dissolved pores(38.7-46.4%),which improves the porosity of reservoirs at a depth of 2600-3100 m.Nevertheless,the late dissolution together with carbonate cementation occurred in closed diagenetic system blocks most seepage channels.Furthermore,the relatively high level clay mineral transformation in the YF1 area leads to a higher content of authigenic illite(44-62%)in the formation.Massive authigenic illite severely blocks the pore throats in fine sandstone,reducing permeability.This study offers an insight to the understanding of mud diapir-derived thermal fluid affecting and controlling the quality of reservoirs in some areas of the Yinggehai Basin.

Water-facilitated targeted repair of degraded cathodes for sustainable lithium-ion batteries

Directly repairing end-of-life lithium-ion battery cathodes poses significant chal-lenges due to the diverse compositions of the wastes.Here,we propose a water-facilitated targeted repair strategy applicable to various end-of-life batches and cathodes.The process involves initiating structural repair and reconstruct-ing particle morphology in degraded LiMn_(2)O_(4)(LMO)through an additional thermal drive post-ambient water remanganization,achieving elemental repair.Compared to solid-phase repair,the resulting LMO material exhibits superior electrochemical and kinetic characteristics.The theoretical analysis highlights the impact of Mn defects on the structural stability and electron transfer rate of degraded materials.The propensity of Mn ions to diffuse within the Mn layer,specifically occupying the Mn 16d site instead of the Li 8a site,theoretically sup-ports the feasibility of ambient water remanganization.Moreover,this method proves effective in the relithiation of degraded layered cathode materials,yielding single crystals.By combining low energy consumption,environmental friendli-ness,and recyclability,our study proposes a sustainable approach to utilizing spent batteries.This strategy holds the potential to enable the industrial direct repair of deteriorated cathode materials.

自愈合导电复合水凝胶用于监测人体运动和3D细胞培养

导电水凝胶已在多个领域崭露头角,因为它具备将外界压力和形变转化为电信号的能力,可实现对物理和化学刺激的灵敏感知.然而,在导电水凝胶的研发中,需要克服平衡导电性和机械强度的挑战.本项工作中,为了提高导电水凝胶的力学性能,我们采用了多重策略.首先,引入了木质素-丹宁酸(lignin-TA)颗粒作为物理交联剂,同时充分利用羟丙基纤维素分子的多羟基结构,促进水凝胶半互穿聚合物网络的形成.随后,通过利用Fe^(3+)离子和TA分子之间的静电力和金属配位相互作用,进一步增强了聚合物网络之间的键合强度,提高了水凝胶的导电性.最终,所制备的导电水凝胶以其独特的网络结构,成功融合了物理和化学键的特性,并展现出卓越的自粘附、自愈合能力、电机械性能和生物相容性.这使其成为一个可用于监测人体活动和细胞增殖的理想材料.

Preparation and photocatalytic activity of Fe3O4@SiO2@ZnO:La

In this study,Fe3 O4@SiO2@ZnO:La microspheres were successfully prepared.The microspheres have the advantages of both ZnO doped with La and the Fe3 O4@SiO2 structure such that the former improves the photocatalytic activity of ZnO and the latter can be reused.The X-ray diffraction(XRD),a field emission scanning electron microscope(SEM),a field emission transmission electron microscope(TEM),X-ray photoelectron spectroscopy(XPS),and a vibrating sample magnetometer(VSM)were used to characterize Fe3 O4@SiO2@ZnO:La microspheres.Methyl orange was used as the model molecule to study the effect of the Zn2+concentration and the doping amount of La on the photocatalytic activity of Fe3 O4@SiO2@ZnO:La microspheres.Results show that in the synthesis of Fe3 O4@SiO2@ZnO:La microspheres,photocatalytic activity of the microspheres is enhanced first and weakened later with the increase of Zn2+concentration.In the La doping process,the photocatalytic activity of Fe3 O4@SiO2@ZnO:La microspheres is enhanced with the increase in the La doping amount.The magnetic photocatalysts not only have high photocatalytic activity,but also can be reused.After being reused five times,the photocatalyst’s degradation rate of methyl orange is still as high as 81%,which shows that magnetic photocatalysts have prospective wider applications in photocatalytic degradation of dye wastewater.