2D van der Waals heterostructures serve as a promising platform to exploit various physical phenomena in a diverse range of novel spintronic device applications. Efficient spin injection is the ...prerequisite for these devices. The recent discovery of magnetic 2D materials leads to the possibility of fully 2D van der Waals spintronics devices by implementing spin injection through the magnetic proximity effect (MPE). Here, the investigation of MPE in 2D graphene/CrBr3 van der Waals heterostructures is reported, which is probed by the Zeeman spin Hall effect through non‐local measurements. Quantitative estimation of the Zeeman splitting field demonstrates a significant MPE field even in a low magnetic field. Furthermore, the observed anomalous longitudinal resistance changes at the Dirac point RXX,D with increasing magnetic field near ν = 0 may be attributed to the MPE‐induced new ground state phases. This MPE revealed in the graphene/CrBr3 van der Waals heterostructures therefore provides a solid physics basis and key functionality for next‐generation 2D spin logic and memory devices.
The magnetic proximity effect (MPE) in 2D graphene/CrBr3 van der Waals heterostructures is probed by the Zeeman spin Hall effect via non‐local transport measurements; estimation of the Zeeman splitting energy demonstrates a significant magnetic proximity exchange field. The newly observed anomalous longitudinal resistances at the Dirac point with magnetic field may be attributed to the new phases of the ground state induced by MPE.
Environmental sustainability represents a major challenge facing our world. Recent advances in synthetic micro/nanomachines have opened new horizons for addressing environmental problems. This review ...article highlights the opportunities and challenges in translating the remarkable progresses in nanomotor technology toward practical environmental applications. It covers various environmental areas that would benefit from these developments, including nanomachine-enabled degradation and removal of major contaminants or nanomotor-based water quality monitoring. Future operations of autonomous intelligent multifunctional nanomachines, monitoring and responding to hazardous chemicals (in a “sense and destroy” mode) and using bioinspired chemotactic search strategies to trace chemical plumes to their source, are discussed, along with the challenges of moving these exciting research efforts to larger-scale pilot studies and eventually to field applications. With continuous innovations, we expect that man-made nano/microscale motors will have profound impact upon the environment.
(CM), is an important ornamental plant and has been widely cultivated all over the world. However, there are no reports on
-based porous biomass carbon (CMBC). In this study, for the first time, CM ...leaves were used to generate porous biomass carbon via NaOH activation. The structures and surface characteristics were determined using scanning electron microscopy, N
adsorption/desorption, TGA, FT-IR, X-ray diffraction, Raman and X-ray photoelectron spectra tests. CMBC has a large SSA (2716 m
/g) and a total pore volume of 1.95 cm
/g. To test the adsorption performance via adsorption experiments, the cationic and synthetic dye, malachite green (MG), was utilized as the adsorption model. The CMBC had a greatest adsorption capacity of 2622.9 mg/g at a pH value of 8 and had a fastest adsorption capacity of 1161.7 mg/g in the first 5 min. To explain MG adsorption into CMBC, the Freundlich isotherm and the pseudo-second-order kinetic model were used. The adsorption mechanism of MG was also investigated. After 10 cycles, the adsorption efficiency of CMBC to MG could still reach 85.3%. In summary, CMBC has excellent potential in dyeing wastewater pollution treatment.
Nanomachines offer considerable promise for the treatment of diseases. The ability of man-made nanomotors to rapidly deliver therapeutic payloads to their target destination represents a novel ...nanomedicine approach. Synthetic nanomotors, based on a multitude of propulsion mechanisms, have been developed over the past decade toward diverse biomedical applications. In this review article, we journey from the use of chemically powered drug-delivery nanovehicles to externally actuated (fuel-free) drug-delivery nanomachine platforms, and conclude with future prospects and challenges for such practical propelling drug-delivery systems. As future micro/nanomachines become more powerful and functional, these tiny devices are expected to perform more demanding biomedical tasks and benefit different drug delivery applications.
Surface subsidence caused by underground mining is a major engineering risk in coal mines. Maintaining coal pillars is an effective method of avoiding this risk. In particular, when mining occurs ...under surface buildings, rivers and railways, i.e., in strip mining, maintaining coal pillars is the most effective approach. In strip mining, the most important goal is controlling the stability of the ground stratum. To achieve this objective, the main requirement is to maintain the stability of the coal pillars. Because the safety of a mine is determined by the stability of its coal pillars, many methods to analyze pillar stability have been proposed.
To determine distribution of severe acute respiratory syndrome coronavirus 2 in hospital wards in Wuhan, China, we tested air and surface samples. Contamination was greater in intensive care units ...than general wards. Virus was widely distributed on floors, computer mice, trash cans, and sickbed handrails and was detected in air ≈4 m from patients.
Soil-rock mixtures (S-RM) are widely distributed in mountainous regions, and there are different genetic types and scales of S-RM slopes. The stability of these slopes is very important for slope ...safety during the construction and operation of engineering projects. Since the mechanical properties of an S-RM are mainly dominated by its random component, accurately investigating the structure of an S-RM slope is the fundamental basis for evaluating the mechanism of a landslide. In this paper, in situ direct shear tests are used to obtain the “soil” strength parameters of the S-RM, the microtremor survey method (MSM) is introduced to detect the S-RM slope and the numerical method of FEM is utilised to simulate the failure characteristics and stability of the S-RM slope. Based on the MSM, the strata structure and proportions of solitary rock blocks in the S-RM slope are investigated, and three possible models of the S-RM slope are established. By using the strength reduction method in numerical simulations, the potential failure surface and stability of a slope of homogeneous soil and that with solitary rock blocks are discussed. The study results show that the MSM is an effective method to estimate the proportion of rock blocks in the S-RM slope. The presence of solitary rock blocks makes the slope potential slide surface complicated. The factor of safety of the S-RM slope is higher than that of the homogeneous soil slope, the rock blocks at the toe of the slope are favourable for slope stability and the rock blocks near the surface of the slope squeeze the lower soil and improve the safety factor of the slope.
In this study, a novel, halogen-free, formaldehyde-free, organic phosphorus-based flame retardant, ammonium salt of hexamethylenediamine-N,N,N′,N′-tetra(methylphosphonic acid) (AHDTMPA), was ...synthesized using urea and hexamethylenediamine-N,N,N′,N′-tetra(methylphosphonic acid) (HDTMPA). AHDTMPA reacted with the O-6 hydroxyls of glucose residues in the cellulose of cotton fabric to form P–O–C covalent bonds. This ability was confirmed by Fourier-transform infrared (FTIR) spectroscopy, attenuated total reflection FTIR spectroscopy, and X-ray diffraction. Cotton fabric treated with 70 g/L AHDTMPA had a limiting oxygen index (LOI) value of 36.0 %, which remained relatively stable after 50 laundering cycles with a 28.0 % LOI value. The surface morphology and thermal stability of treated cotton fabrics were investigated using scanning electron microscopy and thermogravimetric analysis (TGA), respectively. TGA showed that AHDTMPA could exhibit flame retardancy at temperatures lower than the pyrolysis temperature of cotton fabrics. Additionally, the cotton fabric was treated with AHDTMPA through a pad-cure process, as its ease of operation, high efficiency, and excellent application made it an attractive treatment.
Ninety percent of clinical drug development fails despite implementation of many successful strategies, which raised the question whether certain aspects in target validation and drug optimization ...are overlooked? Current drug optimization overly emphasizes potency/specificity using structure‒activity-relationship (SAR) but overlooks tissue exposure/selectivity in disease/normal tissues using structure‒tissue exposure/selectivity–relationship (STR), which may mislead the drug candidate selection and impact the balance of clinical dose/efficacy/toxicity. We propose structure‒tissue exposure/selectivity–activity relationship (STAR) to improve drug optimization, which classifies drug candidates based on drug's potency/selectivity, tissue exposure/selectivity, and required dose for balancing clinical efficacy/toxicity. Class I drugs have high specificity/potency and high tissue exposure/selectivity, which needs low dose to achieve superior clinical efficacy/safety with high success rate. Class II drugs have high specificity/potency and low tissue exposure/selectivity, which requires high dose to achieve clinical efficacy with high toxicity and needs to be cautiously evaluated. Class III drugs have relatively low (adequate) specificity/potency but high tissue exposure/selectivity, which requires low dose to achieve clinical efficacy with manageable toxicity but are often overlooked. Class IV drugs have low specificity/potency and low tissue exposure/selectivity, which achieves inadequate efficacy/safety, and should be terminated early. STAR may improve drug optimization and clinical studies for the success of clinical drug development.
Structure‒tissue exposure/selectivity–activity relationship (STAR) selects drug candidates and balances clinical dose/efficacy/toxicity. Display omitted
Geotechnical engineering is civil engineering constructed in rock and soil and includes three main types: underground, foundation, and slope engineering ...
PDF
