Ting Wang

The Qinling Mountains serve as the main water source for the Weihe River and Hanjiang River. However, the lack of sufficient observational data limits a deeper understanding and the utilization of its water resources. In this study, the Variable Infiltration Capacity (VIC) hydrological model is used to quantitatively analyze runoff changes and their impacts on these rivers, based on meteorological, land use, and elevation data. By using the hydrological parameter transplantation method, a parameterized system was established to simulate runoff variations from 1970 to 2020. Results showed that the total runoff of the Qinling Mountains in Shaanxi Province ranged between 13.26 and 44.47 billion m³/year, with an average perennial runoff of 25.05 billion m³/year. Over the past 51 years, the runoff volume has exhibited a slightly decreasing trend. The average runoff at the northern foothills is 3.56 billion m³/year, which accounts for 62.4% of the natural average runoff of the Weihe River (Huaxian Station). In contrast, the average runoff at the southern foothills is 21.49 billion m³/year, which accounts for 68.1% of the natural average runoff of the Hanjiang River (Huangjiagang Station). The significant variation in water vapor transport from the western equatorial Pacific to the region via the South China Sea has been identified as the primary reason for the changes in runoff. This quantitative study of runoff changes in the Qinling Mountains clarifies their influence on the Weihe River and the Hanjiang River and will provide a basis for the rational usage of ecological water.

In this paper, a mixture of methanol, ethanol, benzene and ethanol were used to extract the leaves of Albizia kalkora (Roxb.) Prain. Then, using Fourier transform infrared (FT-IR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), pyrolysis as chromatography - mass spectrometry, and thermogravimetric analysis (TGA) and other advanced instruments Albizia kalkoraleaves were analyzed to determine their composition. According to the test data, Albizia kalkoraleaves contain epinephrine, trans squalene, stachydrine and other chemical components with high medicinal value, indicating that Albizia kalkoraleaves have potential applications in the pharmaceutical industry. This study has expanded the utilization value of Albizia kalkoratrees and provided technical support for the resource utilization of Albizia kalkoratrees.

Due to the lack of studies on the chemical constituents of Euscaphis japonica bark, Infrared Spectroscopy and Gas Chromatography-Mass Spectrometer techniques were used to analyze the ethanol, phenyl alcohol and methanol extracts from Euscaphis japonica bark, laying a foundation for the efficient utilization of Euscaphis japonica bark. Through experimental verification, different extracts of Euscaphis japonica bark can yield different chemical substances: Stigmast-4-en-3-one, (1R,8a alpha)-1,4a beta-dimethyl -7 beta -(1-hydroxy-1-methylethyl)decalin-1 alpha-ol, lactose, Vitamin E, 9,12-octadecadienoic acid, n-hexadecanoic acid, Arsenous acid Tris(trimethylsilyl)ester 4-hydroxy-3-methoxycianamylic alcohol et al. It was determined that most of the chemicals in Euscaphis japonica bark are soluble in ethanol reagents. According to the relevant mass spectrometry data, Euscaphis japonica bark contains useful pharmaceutical ingredients and chemical raw materials and has broad development prospects.

Three different Co-MOFs, [Co₃(L)₂(DPDP)]_n (1), [Co(HL)(DPDP)]_n (2) and {[Co(HL)(1/2DPDP)₃(H₂O)]·H₂O}_n (3) (H₃L = 4,4′,4′′-(nitrilotris(methylene))tribenzoic acid, DPDP = 4,4′-(2,5-dibutoxy-1,4-phenylene)dipyridine) have been co-crystallized in a one-pot reaction. Based on the significant differences between the three structures, we adopt solvents to ultimately regulate acquisition of pure crystals of the three compounds.

Abstract:  Real‐time spectroscopic methods can provide a valuable window into food manufacturing to permit optimization of production rate, quality and safety. There is a need for cutting edge sensor technology directed at improving efficiency, throughput and reliability of critical processes. The aim of the research was to evaluate the feasibility of infrared systems combined with chemometric analysis to develop rapid methods for determination of sugars in cereal products. Samples were ground and spectra were collected using a mid‐infrared (MIR) spectrometer equipped with a triple‐bounce ZnSe MIRacle attenuated total reflectance accessory or Fourier transform near infrared (NIR) system equipped with a diffuse reflection‐integrating sphere. Sugar contents were determined using a reference HPLC method. Partial least squares regression (PLSR) was used to create cross‐validated calibration models. The predictability of the models was evaluated on an independent set of samples and compared with reference techniques. MIR and NIR spectra showed characteristic absorption bands for sugars, and generated excellent PLSR models (sucrose: SEP < 1.7% and r > 0.96). Multivariate models accurately and precisely predicted sugar level in snacks allowing for rapid analysis. This simple technique allows for reliable prediction of quality parameters, and automation enabling food manufacturers for early corrective actions that will ultimately save time and money while establishing a uniform quality. Practical Application:  The U.S. snack food industry generates billions of dollars in revenue each year and vibrational spectroscopic methods combined with pattern recognition analysis could permit optimization of production rate, quality, and safety of many food products. This research showed that infrared spectroscopy is a powerful technique for near real‐time (approximately 1 min) assessment of sugar content in various cereal products.

Ultrasonic surface rolling extrusion (USRE) processing is applied on quenched and tempered 40Cr. Microstructure observations of USRE specimen surfaces indicate that the processing can both get nano-structured layers, with grain size of 3～7 nm, and reduce the surface roughness to 0.05 μm; plastic flow is formed from top surface to about 200 μm deep with graded distribution of grain size. Tests of mechanical properties show that microhardness of USRE specimen surface is increased by 63%; residual stress at the top surface can reach to –846 MPa and depth of residual stress layer is more than 1 mm. It has been determined by contrast wear test that USRE can reduce friction coefficient and improve the wear-resistant property.