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Granular activated carbon (GAC) has proven to be an effective adsorbent for removing the chemical warfare agent sarin (GB) and simulants like Dimethyl methylphosphonate (DMMP). However, it comes with certain limitations, including inadequate contact efficiency, notable mass transfer resistance, and lower bed utilization efficiency. This study synthesized steel fiber-entrapped activated carbon composites (SFEACs), which exhibited a maximum adsorption capacity of 285.3 mg/g at 303 K. Compared with the packed bed (PB) filled with GAC, while the adsorption capacity of SFEACS decreased, there was a substantial increase in the adsorption mass transfer rate. These SFEACs were combined with GAC to create a structural fixed bed (SFB), which demonstrated excellent performance in DMMP removal. Under identical experimental conditions, the DMMP breakthrough curve of SFB exhibited a steeper profile compared to the packed bed (PB) filled with GAC at the same bed height, and the breakthrough time against DMMP vapor could be extended by 13.8%. Furthermore, the adsorption rate constant of the Yoon-Nelson model increased by more than 17.6%, and the unused bed length, according to the Wheeler–Jonas model, decreased by more than 14%. [ABSTRACT FROM AUTHOR]

The prediction of drug combinations is of great clinical significance. In many diseases, such as high blood pressure, diabetes, and stomach ulcers, the simultaneous use of two or more drugs has shown clear efficacy. It has greatly reduced the progression of drug resistance. This review presents the latest applications of methods for predicting the effects of drug combinations and the bioactivity databases commonly used in drug combination prediction. These studies have played a significant role in developing precision therapy. We first describe the concept of synergy. we study various publicly available databases for drug combination prediction tasks. Next, we introduce five algorithms applied to drug combinatorial prediction, which include traditional machine learning methods, deep learning methods, mathematical methods, systems biology methods and search algorithms. In the end, we sum up the difficulties encountered in prediction models. [ABSTRACT FROM AUTHOR]

Cyanogen chloride (CNCl) is highly toxic and volatile, and it is difficult to effectively remove via porous substances such as activated carbon due to the weak interaction between CNCl and the adsorbent surface. Developing a highly effective elimination material against CNCl is of great importance in military chemical protection. In this work, a new metal-organic framework (MOF) CuBTC@PA-PEI (polyacrylate-polyethyleneimine) composite was prepared and exhibited excellent CNCl elimination performance in the breakthrough tests. PEI was used for the functionalization of PA with amino groups, which is beneficial to anchor with metal ions of MOF. Afterward, the growth of MOF occurred on the surface and in the pores of the matrix by molecular self-assembly via our newly proposed stepwise impregnation layer-by-layer growth method. Breakthrough tests were performed to evaluate the elimination performance of the composites against CNCl. Compared with the pristine CuBTC powder, the CuBTC@PA-PEI composite exhibited better adsorption capacity and a longer breakthrough time. By compounding with the PA matrix, a hierarchically porous structure of CuBTC@PA-PEI composite was constructed, which provides a solution to the mass transfer problem of pure microporous MOF materials. It also solves the problems of MOF molding and lays a foundation for the practical application of MOF. [ABSTRACT FROM AUTHOR]

NH3 is a typical alkaline gaseous pollutant widely derived from industrial production and poses great risks to humans and other biota. Metal-organic frameworks (MOFs) have excellent adsorption capacities relative to materials traditionally used to adsorb NH3. However, in practice, applications of MOFs as adsorbents are restricted because of its powder form. We prepared a polyamide (PA) macroporous polyester substrate using an emulsion template method and modified the surface with polyethylenimine (PEI) to improve the MOF growth efficiency on the substrate. The difficulty of loading the MOF because of the fast nucleation rate inside the PA macroporous polyester substrate was solved using a stepwise impregnation layer-by-layer (LBL) growth method, and a PA-PEI-MOF303(Al) hierarchical pore composite that very efficiently adsorbed NH3 was successfully prepared. The PA-PEI-MOF303(Al) adsorption capacity for NH3 was 16.07 mmol·g−1 at 298 K and 100 kPa, and the PA-PEI-MOF303(Al) could be regenerated repeatedly under vacuum at 423 K. The NH3 adsorption mechanism was investigated by in situ Fourier transform infrared spectroscopy and by performing two-dimensional correlation analysis. Unlike for the MOF303(Al) powder, the formation of multi-site hydrogen bonds between Al–O–Al/C–OH, N–H, –OH, C=O, and NH3 in PA-PEI-MOF303(Al) was found to be an important reason for efficient NH3 adsorption. This study will provide a reference for the preparation of other MOF-polymer composites. [ABSTRACT FROM AUTHOR]

Nickel-based alloy metal matrix composite (NAMMC) is a new type of composite material which is expected to replace traditional Nickel-base superalloy used in the manufacture of important hot-end components in aerospace, naval ships and industrial gas turbine engines due to its excellent high temperature strength, superior thermal fatigue resistance, high oxidation resistance and thermal corrosion resistance. However, these outstanding properties make it hard to process these materials with conventional manufacturing methods such as forging and machining owing to posing problems of high cost and energy consumptions. Laser additive manufacturing (AM) with a high degree of machining freedom and a high-energy-density laser beam as heat source has been used for processing NAMMC hot-end components with superior performance and complicated structure. Nevertheless, some manufacturing defects of poor bonding, high residual stress, cracking, pore etc. still exist in laser AM NAMMC parts. Therefore, this paper reviews research progress of laser AM NAMMC at present. The control method of manufacturing defect and the effect of reinforcements on the microstructure and mechanical properties of NAMMC are summarized. In addition, the challenges and prospects of laser AM NAMMC in the future are also discussed. [ABSTRACT FROM AUTHOR]

Cyanide gas is highly toxic and volatile and is among the most typical toxic and harmful pollutants to human health and the environment found in industrial waste gas. In the military context, cyanide gas has been used as a systemic toxic agent. In this paper, we review cyanide gas elimination methods, focusing on adsorption and catalysis approaches. The research progress on materials capable of affecting cyanide gas adsorption and catalytic degradation is discussed in depth, and the advantages and disadvantages of various materials are summarized. Finally, suggestions are provided for future research directions with respect to cyanide gas elimination materials. [ABSTRACT FROM AUTHOR]

The effect of volume energy density and deposition energy density on the roughness, porosity, density and hardness of laser beam powder bed fusion (LBPBF) GTD222 Ni-based superalloy was systematically studied. The results showed that the roughness and porosity of the alloy decreased with the increase of the two laser energy densities, while the density and hardness increased. When the volume energy density and the deposition energy density exceeded a threshold value, the density and hardness reached the maximum value and almost remained constant. The volume energy density could be used to estimate the laser conditions for obtaining high-density LBPBF GTD222 alloy more accurately than the deposition energy density. The process parameters for the transformation of the alloy from porous to dense were determined based on the volume energy density. This study provides guidance for the optimization of the process parameters of LBPBF GTD222 alloy. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to compare the bone induction of five kinds of calcium phosphate (Ca-P) biomaterials implanted in mice and explore the vascularization and particle-size-related osteoinductive mechanism. Methods: The following five kinds of Ca-P biomaterials including hydroxyapatite (HA) and/or tricalcium phosphate (TCP) were implanted in the muscle of 30 BALB/c mice (n = 6): 20 nm HA (20HA), 60 nm HA (60HA), 12 µm HA (12HA), 100 nm TCP (100TCP) and 12 µm HA + 100 nm TCP (HATCP). Then, all animals were put on a treadmill to run 30 min at a 6 m/h speed each day. Five and ten weeks later, three mice of each group were killed, and the samples were harvested to assess the osteoinductive effects by hematoxylin eosin (HE), Masson's trichrome and safranine–fast green stainings, and the immunohistochemistry of the angiogenesis and osteogenesis markers CD31 and type I collagen (ColI). Results: The numbers of blood vessels were 139 ±   29 ,   118   ±   25 ,   78   ±   15 ,   65   ±   14 in groups HATCP, 100TCP, 60HA and 20HA, respectively, which were significantly higher than that of group 12HA (12 ± 5) in week 5 (p < 0.05). The area percentages of new bone tissue were (7.33 ± 1.26)% and (8.49 ±   1.38) % in groups 100TCP and HATCP, respectively, which were significantly higher than those in groups 20HA (3.27 ±   0.38) % and 60HA (3.43 ±   0.27) % (p < 0.05); however, no bone tissue was found in group 12HA 10 weeks after transplantation. The expression of CD31 was positive in new blood vessels, and the expression of ColI was positive in new bone tissue. Conclusions: Nanoscale Ca-P biomaterials could induce osteogenesis in mice muscle, and the osteoinductive effects of TCP were about 124% higher than those of 20HA and 114% higher than those of 60HA. The particle size of the biomaterials affected angiogenesis and osteogenesis. There was a positive correlation between the number of blood vessels and the area percentage of new bone tissue; therefore, osteoinduction is closely related to vascularization. Our results provide an experimental basis for the synthesis of calcium–phosphorus matrix composites and for further exploration of the osteoinductive mechanism. [ABSTRACT FROM AUTHOR]

Laser shock peening (LSP) is an innovative surface treatment process with the potential to change surface microstructure and improve mechanical properties of additively manufactured (AM) parts. In this paper, the influences of LSP on the microstructure and properties of Ti–6Al–4V (Ti64) titanium alloy fabricated via selective laser melting (SLM), as an attractive AM method, were investigated. The microstructural evolution, residual stress distribution and mechanical properties of SLM-built Ti64 samples were characterized before and after LSP. Results show that the SLM sample was composed of single hcp α' phase, which deviates from equilibrium microstructure at room temperature: α + β phases. The LSP significantly refines the grains of α' phase and produces compressive residual stress (CRS) of maximum magnitude up to −180 MPa with a depth of 250 μm. Grain refinement of α' phase is attributed to the complex interaction of dislocations and the intersection of deformation twinning subjected to LSP treatment. The main mechanism of strength and micro-hardness enhancement via LSP is ascribed to the effects of CRS and α' phase grain refinement. [ABSTRACT FROM AUTHOR]