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In this work, negative-capacitance (NC) and local surface plasmon resonance (LSPR) coupled MoS2 phototransistors with a gate stack of HZO/AuNPs/Al2O3/MoS2 are fabricated, and the impacts of Al2O3 interlayer-thickness (T AlO) on the LSPR effect, the tensile strain on MoS2 from the Au nanoparticles (AuNPs), the capacitance matching of the NC effect from Hf0.5Zr0.5O2 (HZO) ferroelectric layer and the optoelectrical properties of the relevant devices are investigated. Through optimizing T AlO, excellent optoelectrical properties of phototransistors with a T AlO of 3 nm are achieved: a subthreshold swing (SS) of 25.76 mV/dec and ultrahigh detectivity of over 1014 Jones under 740 nm illumination. This is primarily because the NC-LSPR coupled structure can achieve an ultra-low SS through capacitance matching and a good interface passivation through optimizing Al2O3 interlayer to maintain effective LSPR and strain effects cross the MoS2 to enhance optical absorption and detection range. This work provides a comprehensive analysis on effective distance range of the non-direct-contacted LSPR effect and its combination with capacitance matching of NC effect, culminating in an optimized NC-LSPR coupled MoS2 phototransistor with a good consistency across an array of 30 devices, and offering a viable solution for the preparation of large-area, high-performance and broad-spectrum response 2D phototransistor array.

[Objective] In order to explore the effects of soil phosphorus (P) fertilizer and salt and their interaction on the plant growth, P nutrition and salt tolerance of alfalfa (Medicago sativa). [Methods] Alfalfa "Gannon Ⅶ" was planted by adding phosphate fertilizer (0, 40, 80, 160 mg/kg, in the form of KH2PO4) and NaCl (0, 0.4, 0.8, 1.6 g/kg) with different concentration gradients to the loess soil. [Results] The aboveground and underground biomass of alfalfa increased with the increase of P application level, but decreased with the increase of NaCl addition level. When P was added, P uptake by plants increased. When P was added at 160 mg/kg, P concentrations in roots, stems, and leaves all reached the maximum. However, the addition of salinity inhibited the absorption of P. When NaCl was added at 1.6 g/kg, P concentrations in roots, stems, and leaves all significantly decreased, when compared with that without NaCl. The content of tartrate in rhizosphere of alfalfa decreased with the increase of P compared with that without P, and the addition of exogenous salt significantly increased the content of tartrate in rhizosphere. The rhizosphere soil pH of most treatments was lower than that of non-rhizosphere pH, the decrease of soil pH under salt stress might increase the availability of soil P and P uptake by plants. A high-dose (160 mg/kg) of P significantly reduced the P-uptake efficiency of P-utilization efficiency of alfalfa. [Conclusion] In summary, there was a significant interaction between soil P fertilization and salinity, and the increase in salinity exacerbated plant P deficiency. Appropriate application of P-fertilizers can improve the salt tolerance of alfalfa and enhance its productivity in saline soils.

Microdroplets have many unique features such as small size and high electric field, therefore they can be accelerated to initiate chemical reactions and even promote some reactions that cannot be carried out in liquid phase. N, N-Dimethylaniline (DMA) is commonly used in medicine as a raw material for the synthesis of pharmaceutical intermediates. At present, the study involving in the detection of DMA is mainly focused on quantitative detection, and there is few reports on oxidation reaction and gas phase dissociation reaction of DMA. In this paper, the oxidation behavior and dissociation reaction of DMA and related compounds were studied by microdroplet spray mass spectrometry and tandem mass spectrometry. It was found that the ultra-high electric field spontaneously generated by microdroplets at the air-water interface can enable the oxidation reaction of DMA and related compounds to form abundant radical cation DMA+·. By changing the reaction distance, carrier gas pressure, injection velocity, sample concentration and substituent groups, the influence of experimental conditions and substituent modes on the generation of DMA+· was explored. The result showed that the presence of electron donor groups is benefit for the stability of radical cations. After the dissociation of DMA+·, the main product ions were generated by elimination of hydrogen radical and a successive elimination of HC≡N via methyl migration reaction. In addition, when the electron-donating CH3 group was connected with DMA, the intensity of related radical cation increased obviously, indicating that the electron-donating groups promoted the migration reaction. In conclusion, the stable transient intermediate DMA+· that is difficult to prepare by other means, was obtained by microdroplet reaction in this study. This method is helpful to deepen the understanding of the chemical promoted oxidation reaction characteristics of water droplets and enriches the rearrangement reaction types of aniline compounds in gas phase dissociation. It is expected that the prepared active species such as high reactivity radical cations will be applied to chemical industry or pharmaceutical fields in the future.

In the unstable conditions of development of the world economy, which occur under the influence of factors of political and economic instability, one of the most important problems of stable functioning and development of the country’s economy is to ensure the stable development of both the kinds of economic activities and enterprises. Since all kinds of economic activity react differently to the instability of the external environment, it is important to analyze the conditions of functioning and the results of the activities of enterprises by the kinds in order to form adequate and adaptive managerial reactions to the tactical and strategic behavior of the latter. The aim of the article is to study and determine the sensitivity of kinds of economic activities to changes in the external environment in order to form adaptive economic behavior of enterprises. In order to achieve this goal, in the course of the research the following scientific methods were used: comparative analysis, graphic analysis, structural-dynamic analysis, coefficient and cluster analysis. The article proposes an algorithmic model of formation of economic behavior of enterprise depending on the level of sensitivity of the certain kind of economic activity. Implementation of the proposed model will allow to form an effective system of managerial decisions on the future behavior of enterprises. The basis for the development of managerial decisions is the analysis of tendencies in the development of kinds of economic activity of the country by the indicator of gross value added, the allocation of cluster groups of kinds of economic activity by the level of their sensitivity. All this will allow to form an effective system of managerial decision-making, which is aimed at maintaining a sustainable attractor of economic development of the enterprise.

In the process of deep geological disposal of high-level radioactive waste, the decay of nuclide will generate a large amount of heat, which is released into the surrounding environment and affects the water-rock interaction of the deep geological environment. In order to explore the impact of temperature on the chemical environment of the deep groundwater in the Xinchang site, the undisturbed groundwater and deep granite samples at the Xinchang site were used to carry out water-rock interaction study at different temperatures. The research results show that the granite sample from borehole BS34 reacts with the undisturbed groundwater. The final pH value of the aqueous phase is between 6.4-8.5, and the TDS is between 1 653.9-1 759.6 mg/L. With the increase in temperature of the reaction system, the concentrations of Na+ and K+ in the aqueous phase increase, resulting from the dissolution of albite and cation exchange for Na+, and the dissolution of K-feldspar for K+, respectively. Meanwhile, the concentrations of Ca2+, Mg2+ and HCO-3 decrease, mainly due to the precipitation of calcite and dolomite. The higher the reaction temperature, the more calcite and dolomite are precipitated.

Objective To discuss the clinicopathological characteristics of cervical cancer patients with lymphatic metastasis, to evaluate lymph node metastasis in cervical cancer patients by combining pelvic MRI enlarged lymph nodes and SCC-Ag, and to analyze the prognostic value of the model. Methods We retrospectively analyzed the data of 124 patients with cervical cancer. The predictive model was established based on the result. Results The depth of interstitial infiltration, serum SCC-Ag change value before and after treatment, lymph node enlargement showed by pelvic MRI, D2-40 and Ki67 were independent risk factors for lymph node metastasis of cervical cancer (P < 0.05). The prediction model of lymph node metastasis: L=the serum SCC-Ag change value+7.127×lymph node enlargement showed by pelvic MRI+5.386×D2-40+5.135×the depth of interstitial infiltration+19.457×Ki67; the sensitivity was 78.6% and specificity was 79.2%. Conclusion The cervical cancer patients with L≥20.8261 should be noticed. Doctors should give them individualized neoadjuvant treatment, and ensure adequate surgical scope. The above lymphatic prediction model has predictive value for preoperative lymph node metastasis.

Nowadays, the global economic environment is full of uncertainties. Affected by the novel coronavirus epidemic, the economies of various countries are developing slowly or falling into recession. In this case, countries face different uncertainties. The article analyzes the economic development direction of China and Ukraine. Judging from the GDP per capita of both Ukraine and China in the past ten years, China has been growing steadily every year, while Ukraine has changed more. Therefore, the article analyzes the strengths and weaknesses of the 12 pillars of the Global Competitiveness Index for the two countries through the period of 2018–2019, an indicator that measures a country’s ability to grow in the medium and long term. It is found that Ukraine has problems in stability and macroeconomic stability, while China has problems in social cohesion and innovation ability, and puts forward corrective opinions to determine the direction of development. In addition, by analyzing the overall ranking of China and Ukraine in the Global Competitiveness Index from 2009 to 2019, it is found that the economic growth capacity of these countries has partially developed in the same direction in the past decade. However, due to the influence of political and macroeconomic factors, the focus of the development of these countries is to hope that the countries will correct the existing problems as soon as possible, formulate corresponding policy plans, and strengthen and ensure the implementation of the relevant policy. In addition, our countries will continue to strengthen the construction of global integration, reduce trade barriers, increase the liquidity of commodities, speed up the processes, promote the circulation of production factors, accelerate economic growth, and enhance competitiveness. The future can be expected.

Plant hormone Abscisic Acid (ABA) plays an important role in regulating plant growth. However, the content of ABA in plant tissues is very low, and rapid and sensitive detection methods are urgently needed. In this study, a rapid and quantitative ABA detection method was established based on aptamer recognition and surface-enhanced Raman spectroscop (SERS). The gold nanoparticles modified by ABA aptamer had the characteristics of SERS signal enhancement and selective recognition, realizing the rapid and sensitive detection of trace ABA in complex plant sample matrix. When ABA molecules appeared in detect system, the aptamer would specifically bind with ABA molecules, and the aptamer folded into G-tetrad structure at same time, which wrapped ABA molecules in the tetrad structure, shortened the distance between ABA molecules and gold nanoparticles, and the enhanced and stable ABA molecules SERS signal were obtained. Under the condition of optimized aptamer concentration at 0.12 µmol/L, different concentrations of ABA solutions in the detection system were detected. Within the concentration range of 0.1－100 µmol/L, the SERS intensity of ABA presented a good linear relationship with the concentration. The detection limit of this method was 0.1 µmol/L and the linear correlation coefficient R2 was 0.9855. The repeatability test of 20 points randomly on SERS substrate showed that the relative standard deviation (RSD) was 6.71%, indicating the stability of SERS substrate was well. Furthermore, the substrate of gold nanoparticles modified by the ABA aptamer terminal with sulfhydryl group (SH-Apt) could be stored in the refrigerator for more than half a year, indicating that the substrate has good stability. Once the preparation of the synthesized SH-Apt modified gold nanoparticles was completed. It could be used on demand without the need to prepare SERS substrate for every detection. In this sense, the constructed aptamer SERS biosensor could realize the rapid and quantitative detection of ABA. The method was used for the determination of ABA in wheat leaves, and the result was in good agreement with the Enzyme Linked Immunosorbent Assay (ELISA) (The max relative error was 9.13%). This biosensor is an exploratory study on the detection of plant hormones by SERS, and the results of the study will have important reference value for the subsequent quantitative and on-site detection of ABA, as well as the detection of other plant hormones.

MicroRNAs (miRNAs) operate as tumor suppressor or carcinogen to regulate cell proliferation, metastasis, invasion, differentiation, apoptosis, and metabolic process. In the present research, we investigated the effect and mechanism of miR-496 in human gastric cancer cells. miR-496 was downregulated in two gastric cancer cell lines, AGS and MKN45, compared with normal gastric epithelial cell line GES-1. miR-496 mimics inhibited the proliferation of AGS cells after the transfection for 48 and 72 h. The migration and invasion of AGS cells were also inhibited by the transfection of miR-496 mimics. miR-496 mimics induced the apoptosis through upregulating the levels of Bax and Active Caspase 3 and downregulating the levels of Bcl-2 and Total Caspase 3. Bioinformatics analysis showed that there was a binding site between miR-496 and Lyn kinase (LYN). miR-496 mimics could inhibit the expression of LYN in AGS cells. LYN overexpression blocked the inhibition of tumor cell growth, as well as the inhibition of AKT/mTOR signaling pathway induced by miR-496. In conclusion, miR-496 inhibited the proliferation through the AKT/mTOR signaling pathway via targeting LYN in gastric cancer cells. Our research provides a new potential target for clinical diagnosis and targeted treatment for gastric cancer.

C38H45N5O5, triclinic, P1‾ (no. 2), a = 11.3541(16) Å, b = 12.1833(17) Å, c = 14.409(2) Å, α = 68.240(2)°, β = 76.613(3)°, γ = 88.873(3)°, V = 1796.0(4) Å3, Z = 2, Rgt(F) = 0.0620, wRref(F2) = 0.2023, T = 296 K.

A novel flexible restrict reducer is proposed. This reducer is a two stages conical cylindrical gear reducer. The setting element of conical gear and cylindrical gear is pre-tighten belleville spring. There is no axial movement of the gears while the gear axial force is lower than the spring force,the location is accuracy.On the contrary,the spring deforms for absorbing energy to avoid permanent deformation applied by direct axial force. The 3 D model of the flexible restrict reducer is built by UG 8. 0 and the transient dynamics analysis under specified load is carried out by the ANSYS Work Bench. The theoretical feasibility of flexible restrict reducer is verified by the simulation result.

A novel self-stabilizing speed transmission used for wind power generation is proposed. It can keep the constant speed of synchronous generator amature under the time-varying speed of wind rotor. The self-stabilizing speed transmission consist of differential gear train,differential mechanism and constant speed motor. The time-varying speed of wind rotor and constant speed of motor are superimposed by the left wheel and right wheel of differential mechanism. The shell of differential mechanical can automatically adjust the output speed of differential gear train to stable. The kinematics analysis for the self-stabilizing speed wind turbine is carried out,and the mass-spring-damper model of the transmission is established for three shafts system with double inputs and single output. The simulation is executed in SIMULINK software with turbulent wind input.The influences on output shaft speed and torque under different inertia,stiffness,damping are discussed. The frequency of the output shaft speed is compared with natural frequency in order to evaluate the possibility of the system resonance.

At present, people are paying more and more attention to the accuracy, convenience, and efficiency of food quality and safety testing. However, many traditional detection methods have some problems such as inconvenient operation, interference factors, and long detection time. Therefore, functionalized magnetic nanomaterials with higher selectivity and sensitivity are widely used in food detection, such as pesticides, veterinary drugs, heavy metals, additives, and synthetic pigments, pathogenic bacteria, and mycotoxins. In this paper, the practical application of functionalized magnetic nanomaterials and their related detection technologies are reviewed, and their future development direction is discussed. Functional magnetic nanomaterials can solve some problems that exist in magnetic nanomaterials to a great extent, making detection more efficient, economical, accurate, rapid and convenient. However, in the future, people still need to further study more stable and efficient magnetic nanomaterials to cope with various complex detection situations.