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In this study, liquid-liquid extraction-solvent assisted flavor evaporation (LLE-SAFE), headspace solid phase microextraction extraction (HS-SPME), gas chromatography-quadrupole-mass spectrometry (GC-Quadrupole-MS), gas chromatography-orbitrap-mass spectrometry (GC-Orbitrap-MS) and gas chromatography-olfactometry (GC-O) were used in combination to identify the volatile components in a fermented hawthorn wine (SBL-J) and a prepared hawthorn wine (FS), and the results of sensory analysis, modified frequency (MF) and odor activity value (OAV) were used to determine the key aroma compounds. Totally 89 aroma compounds were identified by LLE-SAFE/GC-O-MS. In addition, 29 and 38 aroma compounds with MF values of more than 20% were found in SBL-J and FS, respectively. A total of 123 volatile components were detected by HS-SPME/GC-Quadrupole-MS and HS-SPME/GC-Orbitrap-MS and there were 29 and 33 aroma compounds with OAV of greater than 1 (0.1 for esters) identified in SBL-J and FS, respectively. 2-Methybutyl acetate, ethyl hexanoate, ethyl octanoate and phenylethyl alcohol were the key aroma compounds in the two samples. To our knowledge, 2-methybutyl acetate, ethyl isovalerate, (E,E)-2,4-hexadienoic acid ethyl ester and ethyl butyrate, were identified for the first time as the key aroma components of hawthorn wine.

To examine the variances in volatile organic compounds (VOCs) and sensory attributes across various hop cultivars, an analytical approach was employed. Specifically, gas chromatography-ion mobility spectroscopy (GC-IMS), gas chromatography-mass spectrometry (GC-MS), and quantitative descriptive analysis (QDA) were employed to scrutinize the VOCs and sensory characteristics of four distinct hop varieties, namely Magnum, Palisade, Saaz, and Hersbrucker. The outcomes of QDA revealed a diverse array of sensory profiles in the hops, encompassing citrus and non-citrus fruit aromas, woody, floral, herbal, spicy, and green aromas, with noticeable distinctions in sensory attributes discernible among the various hop cultivars. The results showed that 79 VOCs were identified in the GC-IMS spectra of different varieties of hops, including terpenes, alcohols, esters, aldehydes, and ketones. 140 VOCs were identified in the GC-MS spectra of different varieties of hops, including terpenes, alcohols, ketones, esters, acids, and aldehydes, with terpenes and esters emerging as the prevailing constituents in hops. The principal component analysis (PCA) of different hop VOCs was performed to effectively identify the differences among hop varieties. This study can provide a valuable reference for the comprehensive analysis of VOCs and sensory attributes in hops. Furthermore, it contributes theoretical underpinnings to inform the precise application of hops in the context of beer brewing. [ABSTRACT FROM AUTHOR]

The Loess Plateau is an important source of particulate matter pollution in North China. In order to establish and repair shelterbelts and improve their function of inhibiting wind erosion and dust, four typical shelterbelts (Populus simonii, Pinus tabulaeformis Carr., Pinus tabulaeformis Carr. × Populus simonii and Caragana korshinskii Kom.) were selected to investigate the inhibition rate of soil wind-erosion and the reduction rates of PM1, PM2.5 and PM10 by stand type, stand structure and soil properties. A sample plot survey and semi-fixed observation method were used to measure wind speed and particulate matter concentration and to calculate wind protection effect, sand transport rate, vertical flux of particulate matter, wind-erosion inhibition rate and particulate matter reduction rate. The results showed that the Pinus tabulaeformis Carr. forest and Caragana korshinskii Kom. forest had the best windproofing effect, at 2 m (82.9% ± 23.8%) and 0.5 m (54.4% ± 21.5%), respectively. The distribution curve of the sediment flux of shelterbelts is a logarithmic function. The wind-erosion inhibition rate and PM1 reduction rate of the Pinus tabulaeformis Carr. forest were significantly greater than those of other stand types (p < 0.05). The generalized linear mixed model (GLMM) shows that the DBH variation coefficient (CV) can effectively explain the reduction rate of PM1. It is suggested that policies be enacted to add or replace Pinus tabulaeformis Carr. forest in polluted areas to prevent wind erosion and dust. [ABSTRACT FROM AUTHOR]

Sea ice affects the Earth's energy balance and ocean circulation and is crucial to the global climate system. However, research on the decadal variations in the mean sea-level pressure patterns in recent winters (2001–2020) and the characteristics of sea ice motion (SIM) in the Western Arctic region is very limited. In this study, we utilized the Empirical Orthogonal Function (EOF) analysis method to investigate the potential impacts of Arctic Oscillation (AO) and Arctic Dipole (AD) on the Beaufort High (BH) during the period 2001–2020 and discuss the changes in SIM intensity in the Western Arctic. The results indicate that the negative phases of AO and AD are connected with (tend to bring about) a higher BH, strengthening anticyclonic circulation in the Arctic region. Conversely, the positive phases of AO and AD led to the collapse of the BH, resulting in a reversal of sea ice movement. Additionally, during the period 2001–2020, the BH consistently explained 67% of the sea ice motion (had the highest explanatory degree for sea ice advection within the region (weighted average 61.71%)). Meanwhile, the sea ice advection has become more sensitive to change in various atmospheric circulations. This study contributes to an in-depth understanding of the response of sea ice motion to atmospheric circulation in the Western Arctic in recent years, offering more explanations for the anomalous movement of sea ice in the Western Arctic. [ABSTRACT FROM AUTHOR]

[Objective] Available water for irrigation in Hetao irrigation district has been reduced consistently over the past decades. Improving its water management to alleviate soil salinity is critical to sustaining crop production in this region. The purpose of this paper is to seek optimal water-saving irrigation schemes for this region by using process-based models. [Method] The semi-distributed hydrological model (SahysMod) is used in our study. We consider spatial variability of numerous factors in the modelling, which include meteorology, hydrogeology, soil, irrigation and crops. The model is then combined with GIS to simulate the spatiotemporal dynamics of soil water and salt under different scenarios. Data measured from 2007 to 2012 and 2013-2016 were used to calibrate and verify the model, respectively. [Result] ①In a business as usual scenario, the annual drainage decreases first before gradually stabilizing, with the average annual drainage being 531 million m³; salinized lands in the middle and upper reaches of the irrigation district decrease slightly, but increase significantly in the lower reach. ②Considering water-saving in the whole irrigation district and ecological demand for water in the downstream and the Wuliangsuhai lake, the total water diversion from the canal head should be reduced by 15% from the current level. This will save up to 646 million m³ of water. ③If the current irrigation amount remains unchanged, the water utilization coefficient of the canal can be improved 17.6% at the best. ④If the reduction in total water diversion from Yellow River is the same, reducing irrigation amount in the field is the best way to boost salt leaching. In this scenario, reducing irrigation amount should be the priority, followed by improving water utilization coefficient of the canal. [Conclusion] In addition to saving water, considering ecological demand of the downstream for water is also important in optimizing water management in Hetao Irrigation District. [ABSTRACT FROM AUTHOR]

In this paper, we use the coplanar multi-electrode for designing a rod-shaped sensor for measuring the ice thickness. In order to analyze and study mechanism and feasibility of ice thickness measurements using this technique, we use modes of mathematical model derivation and software simulation to study coplanar multi-electrode capacitance sensors. It uses MAXWELL software to simulate the coplanar multi-electrode capacitance sensor under the models which are being approached by three different media, namely ice, air and water. Both mathematical model derivation and simulation results show that the sensor designed with coplanar multi-electrode capacitance can be used to level the automated measurement of sea ice or river ice thickness. The accuracy is ± 1 cm.

Areas subjected to frequent winds show severe farmland degradation and air pollution caused by wind erosion and particulate matter emissions. Biological soil crust (BCS) coverage can inhibit wind erosion. This study used wind tunnels to analyze the wind erosion and particulate matter emissions of algae crusts and moss crusts for different wind speeds and coverage conditions, providing the proportion of particulate matter emission of the total wind erosion under different conditions. Wind erosion of algae crusts was 33% higher than that of moss crusts, and the average emissions of total suspended particles (TSP), PM10, PM2.5, and PM1 were 51%, 64%, 149%, and 167% higher than those of moss crusts. The wind erosion process pairs of the two biological soil crusts both had strong responses to wind speed and coverage, and particulate matter emissions were particularly sensitive to coverage. The average aerodynamic roughness length of moss crusts was 164% higher than that of algae crusts; with increasing wind speed, the aerodynamic roughness length of algae crusts decreased 60% faster than that of moss crusts. The proportion of particulate matter emissions from biological soil crusts in wind erosion was inversely proportional to wind speed and coverage. The particle emission capacity of moss crusts was directly proportional to the particle size and inversely proportional to the coverage. In contrast, the particle emission capacity of algae crust particles was proportional to the particle size. This study provides information for the management of farmland wind erosion and particulate matter emission. [ABSTRACT FROM AUTHOR]