Recent cover crop adoption is associated with small maize and soybean yield losses in the United States.

Cover crops are gaining traction in many agricultural regions, partly driven by increased public subsidies and by private markets for ecosystem services. These payments are motivated by environmental benefits, including improved soil health, reduced erosion, and increased soil organic carbon. However, previous work based on experimental plots or crop modeling indicates cover crops may reduce crop yields. It remains unclear, though, how recent cover crop adoption has affected productivity in commercial agricultural systems. Here we perform the first large-scale, field-level analysis of observed yield impacts from cover cropping as implemented across the US Corn Belt. We use validated satellite data products at sub-field scales to analyze maize and soybean yield outcomes for over 90,000 fields in 2019-2020. Because we lack data on cover crop species or timing, we seek to quantify the yield impacts of cover cropping as currently practiced in aggregate. Using causal forests analysis, we estimate an average maize yield loss of 5.5% on fields where cover crops were used for 3 or more years, compared with fields that did not adopt cover cropping. Maize yield losses were larger on fields with better soil ratings, cooler mid-season temperatures, and lower spring rainfall. For soybeans, average yield losses were 3.5%, with larger impacts on fields with warmer June temperatures, lower spring and late-season rainfall, and, to a lesser extent, better soils. Estimated impacts are consistent with multiple mechanisms indicated by experimental and simulation-based studies, including the effects of cover crops on nitrogen dynamics, water consumption, and soil oxygen depletion. Our results suggest a need to improve cover crop management to reduce yield penalties, and a potential need to target subsidies based on likely yield impacts. Ultimately, avoiding substantial yield penalties is important for realizing widespread adoption and associated benefits for water quality, erosion, soil carbon, and greenhouse gas emissions.

Pt-Doped HfS2 Monolayer as a Novel Sensor and Scavenger for Dissolved Gases (H2, CO2, CH4, and C2H2) in Transformer Oil: A Density Functional Theory Study.

Detecting the types and concentrations of dissolved gases in insulating oil by resistivity-type sensors is an extremely effective means for diagnosing faults in an oil-immersed transformer. However, further breakthroughs and innovations are needed in gas-sensitive materials for preparing high-performance resistivity-type sensors. In this investigation, the application possibility of using Pt-doped HfS2 (Pt-HfS2) as gas-sensitive materials for the detection of dissolved H2, CO2, CH4, and C2H2 in oil has been verified by analyzing the adsorption energy (Ead), differential charge density (DCD), density of states (DOS), frontier molecular orbital, and desorption time based on density functional theory (DFT). The outcomes suggest that the band gap of HfS2 is obviously narrowed after doping Pt at the position of the bridge between the S and Hf atoms, resulting in a significant increase in the conductivity of HfS2. The low adsorption energy implies that there is only weak physical adsorption between Pt-HfS2 and CO2 (-0.783 eV). In contrast, the highly hybridized atomic orbitals of Pt with H2, CH4, and C2H2 indicate that strong chemical adsorption reactions occur. Two-dimensional Pt-HfS2 as a gas sensor has a great monitoring performance for CH4 at 298 K (room temperature). This research serves as theoretical guidelines for probing the application potential of Pt-HfS2 in fault diagnosis and predictive maintenance of an oil-immersed transformer.

Adsorption and Sensing Performances of MoTe2 Monolayers Doped with Pd, Ni, and Pt for SO2 and NH3: A DFT Investigation.

Density functional theory (DFT) calculation was used to study the adsorption and sensing performances of a transition metal atom (TMA) doped MoTe2 monolayer for two industrial toxic and harmful gases, SO2 and NH3, in this study. The adsorption structure, molecular orbital, density of state, charge transfer, and energy band structure were applied to investigate the interaction between the gas and MoTe2 monolayer substrate. The conductivity of the MoTe2 monolayer film doped with TMA (Ni, Pt, Pd) is significantly improved. The original MoTe2 monolayer has poor adsorptive ability for SO2 and NH3, which is physisorption, while for the TMA-doped MoTe2 monolayer, it is significantly enhanced and the adsorption process is chemisorption. All results provide a trustworthy theoretical basis for sensors based on MoTe2 to detect toxic and harmful gases SO2 and NH3. Additionally, it also provides guidance for further research on the transition metal cluster doped MoTe2 monolayer for gas detection.

Enhancement of Adsorption Performance of Gases in Oil on a Cr3-Modified SnS2 Monolayer Based on the First Principles.

Dissolved gas analysis (DGA) is the most commonly used transformer fault diagnosis technology at present. In this paper, according to the method of first principles of density function theory (DFT), the gas-sensitive mechanisms of four oil-soluble characteristic gases (H2, CO, C2H2, C2H4) on intrinsic SnS2 and Cr3-SnS2 were studied. The adsorption energy and electron transfer were calculated, and the density of states, energy bands, and recovery times were analyzed. It was concluded that H2 and C2H4 were physisorbed on the Cr3-SnS2 monolayer, while CO and C2H2 were chemisorbed. It is believed that the Cr3-SnS2 material can be used in gas sensing for CO and C2H2. Cr3-SnS2 is expected to serve as a gas detector for the detection of CO with both a good response and reusability. Therefore, Cr3-SnS2 has very promising applications in the evaluation of the operation of oil-immersed transformers. This study will provide some help and inspiration for the development of the Cr3-SnS2 monolayer in gas-sensitive materials.

Combination of canagliflozin and puerarin alleviates the lipotoxicity to diabetic kidney in mice.

Diabetic kidney disease is one of the most serious complications of diabetes. Although diabetic kidney disease can be effectively controlled through strict blood glucose management and corresponding symptomatic treatment, these therapies cannot reduce its incidence in diabetic patients. The sodium-glucose cotransporter 2 (SGLT2) inhibitors and the traditional Chinese herb "Gegen" have been widely used in diabetes-related therapy. However, it remains unclear whether the combined use of these two kinds of medicines contributes to an increased curative effect on diabetic kidney disease. In this study, we examined this issue by evaluating the efficacy of the combination of puerarin, an active ingredient of Gegen, and canagliflozin, an SGLT2 inhibitor for a 12-week intervention using a mouse model of diabetes. The results indicated that the combination of puerarin and canagliflozin was superior to canagliflozin alone in improving the metabolic and renal function parameters of diabetic mice. Our findings suggested that the renoprotective effect of combined puerarin and canagliflozin in diabetic mice was achieved by reducing renal lipid accumulation. This study provides a new strategy for the clinical prevention and treatment of diabetic kidney disease. The puerarin and SGLT2 inhibitor combination therapy at the initial stage of diabetes may effectively delay the occurrence of diabetic kidney injury, and significantly alleviate the burden of renal lipotoxicity.

Hierarchical WO3-NiO microflower for high sensitivity detection of SF6 decomposition byproduct H2S.

In this work, hierarchical WO3-NiO microflowers have been designed and prepared through a controllable hydrothermal route for high sensitivity detection of H2S produced by SF6 decomposition. The hierarchical flower-like nanostructures assembled with numerous nanosheets were influenced by the introduction of WO3, which is regarded as a significant strategy for improving the gas sensing properties. The synthesized nanostructures were tested by various characterization to investigate the different microstructures of the nanocomposites. The H2S sensing performances of the sensors fabricated with these flower-like nanostructures were measured, which indicated that 3.0 at% WO3-NiO microflower based sensor possessed excellent properties such as higher gas responses and more prominent repeatability compared with those of other fabricated sensors. The enhanced performances might be mainly ascribed to the creation of the heterojunction at n-type WO3 and p-type NiO interface, which caused the improvement of the potential barrier and depletion layer. In addition, the larger specific surface area of flower-like nanostructures also possessed abundant sites for surface reaction.

Identification of Hub Genes Using Co-Expression Network Analysis in Breast Cancer as a Tool to Predict Different Stages.

BACKGROUND Breast cancer has a high mortality rate and is the most common cancer of women worldwide. Our gene co-expression network analysis identified the genes closely related to the pathological stage of breast cancer. MATERIAL AND METHODS We performed weighted gene co-expression network analysis (WGCNA) from the Gene Expression Omnibus (GEO) database, and performed pathway enrichment analysis on genes from significant modules. RESULTS A non-metastatic sample (374) of breast cancer from GSE102484 was used to construct the gene co-expression network. All 49 hub genes have been shown to be upregulated, and 19 of the 49 hub genes are significantly upregulated in breast cancer tissue. The roles of the genes CASC5, CKAP2L, FAM83D, KIF18B, KIF23, SKA1, GINS1, CDCA5, and MCM6 in breast cancer are unclear, so in order to better reveal the staging of breast cancer markers, it is necessary to study those hub genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes indicated that 49 hub genes were enriched to sister chromatid cohesion, spindle midzone, microtubule motor activity, cell cycle, and something else. Additionally, there is an independent data set - GSE20685 - for module preservation analysis, survival analysis, and gene validation. CONCLUSIONS This study identified 49 hub genes that were associated with pathologic stage of breast cancer, 19 of which were significantly upregulated in breast cancer. Risk stratification, therapeutic decision making, and prognosis predication might be improved by our study results. This study provides new insights into biomarkers of breast cancer, which might influence the future direction of breast cancer research.

Facile Hydrothermal Synthesis and Enhanced Methane Sensing Properties of Pt-Decorated ZnO Nanosheets.

Pure and Pt-decorated ZnO nanosheets were synthesized via a facile and environment-friendly hydrothermal process, and characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS), respectively. Side-heated chemical gas sensors were fabricated with the synthesized ZnO based powders and their sensing properties to methane CH4, an important characteristic hydrocarbon contaminant extracted from power transformer oil with overheating or discharging fault, were systemically investigated. Interestingly, Pt decoration not only obviously increased the gas response of sensor fabricated with the synthesized ZnO nanosheets to CH4, but also effectively reduced its optimum operating temperature. Its highest response to 50 ppm of CH4 was about 63.45 at 240 °C, which was about two times larger when compared with the pure one. Meanwhile, the Pt-decorated ZnO nanosheets sensor exhibited shorter response-recovery characteristic, good linearity in low concentration range and excellent stability towards CH4. Those superior sensing features indicate the synthesized Pt-decorated ZnO nanosheets is a promising candidate for fabricating high-performance CH4 sensor.

Ni-CNT Chemical Sensor for SF6 Decomposition Components Detection: A Combined Experimental and Theoretical Study.

SF6 decomposition components detection is a key technology to evaluate and diagnose the insulation status of SF6-insulated equipment online, especially when insulation defects-induced discharge occurs in equipment. In order to detect the type and concentration of SF6 decomposition components, a Ni-modified carbon nanotube (Ni-CNT) gas sensor has been prepared to analyze its gas sensitivity and selectivity to SF6 decomposition components based on an experimental and density functional theory (DFT) theoretical study. Experimental results show that a Ni-CNT gas sensor presents an outstanding gas sensing property according to the significant change of conductivity during the gas molecule adsorption. The conductivity increases in the following order: H2S > SOF2 > SO2 > SO2F2. The limit of detection of the Ni-CNT gas sensor reaches 1 ppm. In addition, the excellent recovery property of the Ni-CNT gas sensor makes it easy to be widely used. A DFT theoretical study was applied to analyze the influence mechanism of Ni modification on SF6 decomposition components detection. In summary, the Ni-CNT gas sensor prepared in this study can be an effective way to evaluate and diagnose the insulation status of SF6-insulated equipment online.

Synthesis, Characterization and Enhanced Sensing Properties of a NiO/ZnO p-n Junctions Sensor for the SF6 Decomposition Byproducts SO2, SO2F2, and SOF2.

The detection of partial discharge and analysis of the composition and content of sulfur hexafluoride SF6 gas components are important to evaluate the operating state and insulation level of gas-insulated switchgear (GIS) equipment. This paper reported a novel sensing material made of pure ZnO and NiO-decorated ZnO nanoflowers which were synthesized by a facile and environment friendly hydrothermal process for the detection of SF6 decomposition byproducts. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were used to characterize the structural and morphological properties of the prepared gas-sensitive materials. Planar-type chemical gas sensors were fabricated and their gas sensing performances toward the SF6 decomposition byproducts SO2, SO2F2, and SOF2 were systemically investigated. Interestingly, the sensing behaviors of the fabricated ZnO nanoflowers-based sensor to SO2, SO2F2, and SOF2 gases can be obviously enhanced in terms of lower optimal operating temperature, higher gas response and shorter response-recovery time by introducing NiO. Finally, a possible gas sensing mechanism for the formation of the p-n junctions between NiO and ZnO is proposed to explain the enhanced gas response. All results demonstrate a promising approach to fabricate high-performance gas sensors to detect SF6 decomposition byproducts.

[Measurement of Trace C2H6 Based on Optical-Feedback Cavity-Enhanced Absorption Spectroscopy].

Ethane is one of major fault characteristic gases dissolved in power transformer, the detection of Ethane with high accuracy and sensitivity is the key of dissolved gas analysis. In this paper, based on optical feedback theory and cavity-enhanced absorption spectroscopy, combined with quantum cascade laser, a detection system for dissolved gas C2 H6 in transformer oil was built up. Based on the symmetry of the individual cavity modes, the phase matching of returning light in resonance with the cavity was achieved through LabVIEW codes. The optical feedback effect that the emitted light return to the laser cavity after a small delay time and lock to the resonance frequency of cavity, even and odd modes effect that the higher modes and lower modes structure will build up alternatively, and threshold current lowering effect of about 1.2 mA were studied and achieved. By cavity ring-down spectroscopy, the effective reflectivity of 99.978% and cavity finesse of 7 138.4 is obtained respectively. The frequency selectivity is 0.005 2 cm(-1). With an acquisition time of 1s, this optical system allows detection for the PQ3 band of C2 H6 with high accuracy of 95.72% ± 0.17% and detection limit of (1.97 ± 0.06) x 10(-3) µL x L(-1) at atmospheric pressure and temperature of 20 degrees C, which lays a foundation for fault diagnose from dissolved gas analysis.

Hydrothermal synthesis and acetylene sensing properties of variety low dimensional zinc oxide nanostructures.

Various morphologies of low dimensional ZnO nanostructures, including spheres, rods, sheets, and wires, were successfully synthesized using a simple and facile hydrothermal method assisted with different surfactants. Zinc acetate dihydrate was chosen as the precursors of ZnO nanostructures. We found that polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), glycine, and ethylene glycol (EG) play critical roles in the morphologies and microstructures of the synthesized nanostructures, and a series of possible growth processes were discussed in detail. Gas sensors were fabricated using screen-printing technology, and their sensing properties towards acetylene gas (C2H2), one of the most important arc discharge characteristic gases dissolved in oil-filled power equipments, were systematically measured. The ZnO nanowires based sensor exhibits excellent C2H2 sensing behaviors than those of ZnO nanosheets, nanorods, and nanospheres, indicating a feasible way to develop high-performance C2H2 gas sensor for practical application.

Hydrothermal synthesis of various hierarchical ZnO nanostructures and their methane sensing properties.

Hierarchical flower-like ZnO nanorods, net-like ZnO nanofibers and ZnO nanobulks have been successfully synthesized via a surfactant assisted hydrothemal method. The synthesized products were characterized by X-ray powder diffraction and field emission scanning electron microscopy, respectively. A possible growth mechanism of the various hierarchical ZnO nanostructures is discussed in detail. Gas sensors based on the as-prepared ZnO nanostructures were fabricated by screen-printing on a flat ceramic substrate. Furthermore, their gas sensing characteristics towards methane were systematically investigated. Methane is an important characteristic hydrocarbon contaminant found dissolved in power transformer oil as a result of faults. We find that the hierarchical flower-like ZnO nanorods and net-like ZnO nanofibers samples show higher gas response and lower operating temperature with rapid response-recovery time compared to those of sensors based on ZnO nanobulks. These results present a feasible way of exploring high performance sensing materials for on-site detection of characteristic fault gases dissolved in transformer oil.

Research status of gas sensing performance of MoTe2-based gas sensors: A mini review.

Transition metal dichalcogenides (TMDs) have been widely explored for their excellent gas sensing properties, especially high sensitivity and stability at room temperature. MoTe2 exhibits good sensitivity and selectivity to some nitrogen-containing gases (i.e., NO2, NH3) and has received extensive attention in gas sensing. In addition, increasingly complex production environments place demands on high-quality gas sensors. Therefore, worldwide efforts are devoted to designing and manufacturing MoTe2-based gas sensors with faster response and recovery speed. This paper summarizes the research progress of MoTe2-based gas sensing, focuses on the practical measures to improve the response and recovery speed of MoTe2-based sensors, and discusses the mechanism. This provides guidance for exploring higher performance MoTe2 sensors.

Adsorption and Sensing Performances of Pristine and Au-Decorated Gallium Nitride Monolayer to Noxious Gas Molecules: A DFT Investigation.

In this study, the adsorption of noxious gas molecules (NO, Cl2, and O3) on GaN and Au-decorated GaN was systematically scrutinized, and the adsorption energy, bond length, charge, density of state (DOS), partial density of state (PDOS), electron deformation density (EDD), and orbitals were analyzed by the density functional theory (DFT) method. It is found that the interaction between NO and pristine GaN is physical adsorption, while GaN chemically reacts with Cl2 and O3. These observations suggest that pristine GaN may be a candidate for the detection of Cl2 and O3. The highly activated Au-decorated GaN can enhance the adsorption performance toward NO and convert the physical adsorption for NO into chemical adsorption, explaining the fact that precious metal doping is essential for regulating the electronic properties of the substrate material. This further confirms the well-established role of Au-decorated GaN in NO gas-sensing applications. In addition, the adsorption performance of Au-decorated GaN for Cl2 and O3 molecules is highly improved, which provides guidance to scavenge toxic gases such as Cl2 and O3 by the Au-decorated GaN material.

Gas Sensing Mechanism and Adsorption Properties of C2H4 and CO Molecules on the Ag3-HfSe2 Monolayer: A First-Principle Study.

The detection of dissolved gases in oil is an important method for the analysis of transformer fault diagnosis. In this article, the potential-doped structure of the Ag3 cluster on the HfSe2 monolayer and adsorption behavior of CO and C2H4 upon Ag3-HfSe2 were studied theoretically. Herein, the binding energy, adsorption energy, band structure, density of state (DOS), partial density of state (PDOS), Mulliken charge analysis, and frontier molecular orbital were investigated. The results showed that the adsorption effect on C2H4 is stronger than that on CO. The electrical sensitivity and anti-interference were studied based on the bandgap and adsorption energy of gases. In particular, there is an increase of 55.49% in the electrical sensitivity of C2H4 after the adsorption. Compared to the adsorption energy of different gases, it was found that only the adsorption of the C2H4 system is chemisorption, while that of the others is physisorption. It illustrates the great anti-interference in the detection of C2H4. Therefore, the study explored the potential of HfSe2-modified materials for sensing and detecting CO and C2H4 to estimate the working state of power transformers.

First-Principles Study of Au-Doped InN Monolayer as Adsorbent and Gas Sensing Material for SF6 Decomposed Species.

As an insulating medium, sulfur hexafluoride (SF6) is extensively applied to electrical insulation equipment to ensure its normal operation. However, both partial discharge and overheating may cause SF6 to decompose, and then the insulation strength of electrical equipment will be reduced. The adsorption properties and sensing mechanisms of four SF6 decomposed components (HF, SO2, SOF2 and SO2F2) upon an Au-modified InN (Au-InN) monolayer were studied in this work based on first-principles theory. Meanwhile, the adsorption energy (Ead), charge transfer (QT), deformation charge density (DCD), density of states (DOS), frontier molecular orbital and recovery property were calculated. It can be observed that the structures of the SO2, SOF2 and SO2F2 molecules changed significantly after being adsorbed. Meanwhile, the Ead and QT of these three adsorption systems are relatively large, while that of the HF adsorption system is the opposite. These phenomena indicate that Au-InN monolayer has strong adsorption capacity for SO2, SOF2 and SO2F2, and the adsorption can be identified as chemisorption. In addition, through the analysis of frontier molecular orbital, it is found that the conductivity of Au-InN changed significantly after adsorbing SO2, SOF2 and SO2F2. Combined with the analysis of the recovery properties, since the recovery time of SO2 and SO2F2 removal from Au-InN monolayer is still very long at 418 K, Au-InN is more suitable as a scavenger for these two gases rather than as a gas sensor. Since the recovery time of the SOF2 adsorption system is short at 418 K, and the conductivity of the system before and after adsorption changes significantly, Au-InN is an ideal SOF2 gas-sensing material. These results show that Au-InN has broad application prospects as an SO2, SOF2 and SO2F2 scavenger and as a resistive SOF2 sensor, which is of extraordinary meaning to ensure the safe operation of power systems. Our calculations can offer a theoretical basis for further exploration of gas adsorbent and resistive sensors prepared by Au-InN.

First-Principles Insight into Pd-Doped C3N Monolayer as a Promising Scavenger for NO, NO2 and SO2.

The adsorption and sensing behavior of three typical industrial toxic gases NO, NO2 and SO2 by the Pd modified C3N monolayer were studied in this work on the basic first principles theory. Meanwhile, the feasibility of using the Pd doped C3N monolayer (Pd-C3N) as a sensor and adsorbent for industrial toxic gases was discussed. First, the binding energies of two doping systems were compared when Pd was doped in the N-vacancy and C-vacancy sites of C3N to choose the more stable doping structure. The result shows that the doping system is more stable when Pd is doped in the N-vacancy site. Then, on the basis of the more stable doping model, the adsorption process of NO, NO2 and SO2 by the Pd-C3N monolayer was simulated. Observing the three gases adsorption systems, it can be found that the gas molecules are all deformed, the adsorption energy (Ead) and charge transfer (QT) of three adsorption systems are relatively large, especially in the NO2 adsorption system. This result suggests that the adsorption of the three gases on Pd-C3N belongs to chemisorption. The above conclusions can be further confirmed by subsequent deformable charge density (DCD) and density of state (DOS) analysis. Besides, through analyzing the band structure, the change in electrical conductivity of Pd-C3N after gas adsorption was studied, and the sensing mechanism of the resistive Pd-C3N toxic gas sensor was obtained. The favorable adsorption properties and sensing mechanism indicate that the toxic gas sensor and adsorbent prepared by Pd-C3N have great application potential. Our work may provide some guidance for the application of a new resistive sensor and gas adsorbent Pd-C3N in the field of toxic gas monitoring and adsorption.

The Adsorption of H2 and C2H2 on Ge-Doped and Cr-Doped Graphene Structures: A DFT Study.

In order to find an excellent sensing material for dissolved gases in transformer oil, the adsorption structures of intrinsic graphene (IG), Ge-doped graphene (GeG), and Cr-doped graphene (CrG) to H2 and C2H2 gas molecules were built. It was found that the doping site right above C atom (T) was the most stable structure by studying three potential doping positions of the Ge and Cr atom on the graphene surface. Then, the structural parameters, density of states, and difference state density of these adsorption systems were calculated and analyzed based on the density functional calculations. The results show that the adsorption properties of GeG and CrG systems for H2 and C2H2 are obviously better than the IG system. Furthermore, by comparing the two doping systems, CrG system exhibits more outstanding adsorption performances to H2 and C2H2, especially for C2H2 gas. Finally, the highest adsorption energy (-1.436 eV) and the shortest adsorption distance (1.981 Å) indicate that Cr-doped graphene is promising in the field of C2H2 gas-sensing detection.

First-Principle Insight into Ga-Doped MoS2 for Sensing SO2, SOF2 and SO2F2.

First-principle calculations were carried out to simulate the three decomposition gases (SO2, SOF2, and SO2F2) of sulfur hexafluoride (SF6) on Ga-doped MoS2 (Ga-MoS2) monolayer. Based on density functional theory (DFT), pure MoS2 and multiple gas molecules (SF6, SO2, SOF2, and SO2F2) were built and optimized to the most stable structure. Four types of Ga-doped positions were considered and it was found that Ga dopant preferred to be adsorbed by the top of Mo atom (TMo). For the best adsorption effect, two ways of SO2, SOF2, and SO2F2 to approach the doping model were compared and the most favorable mode was selected. The adsorption parameters of Ga-MoS2 and intrinsic MoS2 were calculated to analyze adsorption properties of Ga-MoS2 towards three gases. These analyses suggested that Ga-MoS2 could be a good gas-sensing material for SO2 and SO2F2, while it was not suitable for SOF2 sensing due to its weak adsorption. This work provides a theoretical basis for the development of Ga-MoS2 materials with the hope that it can be used as a good gas-sensing material for electrical equipment.