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The primary purpose of the research is to explore triaxial contact stresses of the green bus tire including complex rubber materials and rim. An accurate finite element model of the bus tire is constructed using ABAQUS software after verification. The measured and calculated values have good consistency under different tire loads and inflation pressures. The finite element model is applied for quantitative research by changing tire loads, inflation pressures, and rolling conditions. The analysis results show that higher inflation pressure increases vertical contact stress, which requires a reasonable balance between high load and high inflation pressure. When the inflation pressure increases, the position of the maximum longitudinal contact stress shifts forward, and the maximum transverse contact stress shifts inboard in the transverse direction. When the tire load becomes larger at the free rolling condition, the position of the maximum vertical contact stress moves forward, and the position at the full braking condition is more advanced under the same load conditions. Overload not only causes great damage to the tire during the braking condition but also accelerates the appearance of the rutting and shoving of the road.

The primary purpose of the research is to explore the combined effects of the tire loading velocity (LV) and the nonlinear cross-anisotropic properties of granular base on critical pavement responses. An accurate finite element (FE) model of the pavement structure is constructed using ABAQUS software after verification. The FE model is applied for quantitative research by changing the nonlinear cross-anisotropic characteristic parameters under different LVs, which is done to determine the relationship between the critical strain responses and LVs under nonlinear cross-anisotropic properties. The transverse tensile strain is found to be exerted on the pavement for a longer amount of time than the longitudinal tensile strain. It also found that the critical longitudinal, transverse, and shear strains can be described as having exponential relationships. The exponent coefficients indicate that the influences of the LV on these three types of strains are analogical. In other words, with the increase of tire velocity, the critical strains decay exponentially. The LV is found to have a limited impact on the compressive strain under the same nonlinear cross-anisotropic properties. However, the effects of nonlinear cross-anisotropic properties on the compressive strain at the top of the subgrade are obvious.

A 26-year, long-term record of atmospheric methane (CH4) measured in situ at the Mount Waliguan (WLG) station, the only World Meteorological Organization (WMO) and Global Atmosphere Watch (GAW) global station in inland Eurasia, is presented. Overall, a nearly continuous increase in atmospheric CH4 was observed at WLG, with a yearly growth rate of 5.1±0.1 parts per billion (ppb) per year during 1994–2019, except for some particular periods with near-zero or negative values, e.g., 1999–2000 and 2004–2006. The average CH4 mole fraction was only 1799.0±0.4 ppb in 1994 but increased to about 133 ppb and reached a historic level of 1932.0±0.1 ppb in 2019. The case study in the Tibetan Plateau showed that the atmospheric CH4 increased rapidly. During some special periods, it is even larger than that of city regions (e.g., 6.7±0.2 ppb yr−1 in 2003–2007). Generally, the characteristics of CH4 varied in different observing periods as follows: (i) the diurnal cycle has become apparent and the amplitudes of the diurnal or seasonal cycles increased over time; (ii) the wind sectors with elevated CH4 mole fractions switched from ENE-E-ESE-SE-SSE sectors (wind directions) in early periods to NNE-NE-ENE-E sectors in later years; (iii) the area of source regions increased as the years progressed, and strong sources shifted from northeast (city regions) to southwest (northern India); and (iv) the annual growth rates in recent years (e.g., 2008–2019) were significantly larger than those in the early periods (e.g., 1994–2007).

The effects of the cross-anisotropy of different materials of the asphalt surface layer and the depth-temperature relationship on pavement responses and damage are investigated. A three-dimensional Finite-Element Model (FEM) of the pavement, which considers the depth-temperature relationship of the surface layer under moving tire load, is developed. Pavement damage models are established to evaluate the damage ratio for primary rutting and fatigue cracking. The results show that the compressive strain at the bottom of the surface layer increases as the temperature increases, and the cross-anisotropy (n-value) decreases, indicating that a decrease in the horizontal modulus of different materials of the surface layer increases the damage ratio for primary rutting at high temperatures. The tensile strain at the bottom of the surface layer declines as the n-value increases to 1. For the same change in the n-value, the rate of change of the damage ratio for fatigue cracking is greater at low temperatures than at high temperatures, demonstrating that the number of allowable load repetitions is more sensitive at low temperatures. In addition, the effect of cross-anisotropy and temperature on the vertical stress are larger on the top of the base than in the subbase and subgrade.

Rhodosporidium toruloides is a useful oleaginous yeast, but lipids production is affected by various factors including nutrients in the culture medium. Herein, the R-ZL2 high-yield mutant strain was used to investigate the effects of different carbon sources (sucrose, glucose, xylose), nitrogen sources (ammonium sulphate, ammonium nitrate), and C/N ratio on lipids production capacity, get the following conclusion (1) Compared with glucose and xylose, sucrose was a superior carbon source for lipids production; (2) When using ammonium sulphate as the nitrogen source, a C/N ratio of 200:1 achieved the highest biomass, lipids production and lipids content (10.7 g/L, 6.32 g/L and 59%, respectively), and lipids produced under different C/N conditions have potential for biodiesel production (except for C/N = 40 and C/N = 80); (3) When using ammonium nitrate as the nitrogen source, a C/N ratio of 200:1 achieved the highest biomass, lipids production and lipids content (12.1 g/L, 8.25 g/L and 65%, respectively), and lipids produced under different C/N ratio conditions have potential for biodiesel production. Thus, a combination of sucrose and ammonium nitrate was optimal for the lipid accumulation in R-ZL2. The findings will lay a foundation for further improving lipids yields.

This study investigated the effects of exogenous salicylic acid (SA) treatment (0, control; 3 mmol L

The marine microalga Nannochloropsis sp. contains various elongases and desaturases that are critical for biosynthesis of polyunsaturated fatty acids. A full-length cDNA encoding a long-chain fatty acid elongase, named NsFAE, was cloned from Nannochloropsis sp.. The open reading frame of NsFAE (GenBank accession no. MF680548) consisted of 1068bp and encoded a predicted protein of 355 amino acids with molecular mass 38.8kDa. The deduced polypeptide showed 43%-44% identity to fatty acyl elongases from other algae. RT-PCR experiments indicated that the NsFAE gene exhibited the highest expression in Nannochloropsis sp. at 72h (i.e., during the third growth stage) and the expression was significantly lower in the other four growth stages. Plasmid pNsFAE-CRISPR and a recombinant DNA fragment (ADH1p-NsFAE-CYCt) were transformed into Saccharomyces cerevisiae strain BY4742 using the CRISPR-Cas system. Yeast transformants containing NsFAE produced three fatty acids not normally present in wild-type BY4742-linoleic acid, linolenic acid and eicosadienoic acid-indicating that NsFAE encodes a functional elongase enzyme.

The contact stress distribution of tire-pavement is generally assumed to be uniformly distributed in circles or rectangles in the pavement design. This simplification can solve some common engineering problems, but it neglects two factors including magnitude and direction of the contact stress. The main purpose of this paper is to analyze the contact stress distribution between the bus tire and the pavement under different driving conditions and pinpoint and compare the critical slip ratio during braking and acceleration. First, a tire-pavement simulated contact model is constructed by ABAQUS. Next, we compare, respectively, contact stresses in the vertical, longitudinal, and transverse directions at various rolling conditions and analyze the longitudinal forces at different slip ratios during braking and acceleration. It is observed that the magnitude, direction, and nonuniform distribution of contact stress are affected by the multiple working conditions while the bus is working. Meanwhile, in the braking and acceleration conditions, the longitudinal force grows rapidly as the slip ratio increases, and then grows slowly and at last decreases when the critical slip ratio is reached. However, the critical slip ratio at the time of braking differs from that at the time of acceleration, and the former is smaller than the latter.

The oleaginous yeast Rhodosporidium toruloides AS 2.1389 is viewed as desirable industrial microorganisms that can accumulate a high content of lipids for biodiesel production. In this study, we attempted to improve lipid accumulation in the yeast Rhodosporidium toruloides by UV irradiation mutagenesis and selection based on lithium chloride tolerance or ethanol-H2O2 tolerance. The biomass concentration, lipid yield and glucose consumption of mutant R. toruloides were determined. The transcription levels of lipid accumulation-related genes in the wild-type and mutant strains were also determined. The lithium chloride-tolerant strain R-ZL2 and the ethanol-H2O2-resistant strain R-ZY13 were generated by UV mutagenesis. The two mutant strains showed greater lipid productivity and lipid yield compared to the wild type. Transcriptional analysis revealed that IDP1, GPD1 and GND were expressed at significantly higher levels in the two high-lipid-producing mutants. In conclusion, lipid productivity and lipid yield in R. toruloides were successfully improved via UV mutagenesis and selection. We also identified some lipid accumulation-related genes for improving lipid productivity through genetic engineering.

In this work, to analyse the changing characteristics of contact stresses in the tyre&ndash, pavement interface and the functional relationship between rolling resistance and the working conditions of truck-bus tyres, a three-dimensional tyre&ndash, pavement model is established and used to predict the distribution of contact stresses and rolling resistance under different working conditions of the tyre, comprising various tyre loads, inflation pressures, and velocities. Results show that the magnitude relationship between transverse and longitudinal contact stresses is related to rolling conditions, and overload and low tyre pressure are important contributors to the wear of the tyre shoulder. In addition, the proposed exponential equation presents a method that can be used to forecast rolling resistance related to the working conditions of the truck-bus tyre, and a similar method can be used to predict the rolling resistances of other types of tyres.

Winter jujube inevitably suffers from rapid oxidation after harvest, leading to quality deterioration. Temperature plays an important role in the ripening and senescence of fruit. This study aimed to investigate the effect of different temperatures on the quality parameters, antioxidant enzyme activities, and antioxidant enzyme-related gene expressions of winter jujube. Jujube fruit were stored at room temperature (RT: 25 °C) and low temperature (LT: 0 °C) for 35 days, respectively. Compared with RT, LT maintained higher firmness and lower respiratory rate, inhibited the increase of weight loss, decay rate, total soluble solids (TSS) and reddening rate, delayed the decrease of titratable acid (TA) and ascorbic acid (AsA) content. LT-stored jujube fruit also showed higher antioxidant enzyme activities and related gene expression (Mn-SOD, APX, and GR, except CAT). We observed a significant correlation between fruit quality parameters and antioxidant enzymes, suggesting that fruit senescence is closely related to antioxidant ability. In short, LT delayed the ripening rate by inducing a series of physiological and molecular reactions, thereby improving antioxidant levels and storage quality.

A 24-year long-term observation of atmospheric CH4 was presented at Mt. Waliguan (WLG) station, the only WMO/GAW global station in inland of Eurasia. Overall, during 1994–2017, continuously increase of atmospheric CH4 was observed at WLG with yearly growth rate of 5.1 ± 0.1 ppb yr−1, although near-zero and even negative growth appeared in some particular periods, e.g., 1999–2000, and 2004–2006. The average CH4 mole fraction was only 1805.8 ± 0.1 ppb in 1995, but unprecedented elevated ~ 100 ppb and reached a historic high of 1903.8 ± 0.1 ppb in 2016. The seasonal averages of atmospheric CH4 at WLG were ordered by summer, winter, autumn and spring, and the correlation slopes of ΔCO/ΔCH4 showed a maximum in summer and minimum in winter, which was almost opposite to other sites in the northern hemisphere, e.g., Mauna Loa, Jungfraujoch, and was caused by regional transport. Strong potential sources at WLG were predominately identified in northeast (cities, e.g., Xining, Lanzhou) and southwest (the Northern India), and air masses from west and northwest regions were accompanied with higher CH4 mole fractions than that from city regions. What is interesting is that obviously changes appeared in different observing periods. Generally, (i) the amplitudes of diurnal or seasonal cycles were continuously increasing over time, (ii) the wind sectors with elevated CH4 moved from ENE- ... -SSE sectors in early periods to NNE- ... -E sectors (city regions) in later years, (iii) the area of source regions was increasing along with the years, and strong sources gradually shifted from northeast to southwest, (iv) the annual growth rates in recent years (e.g., 2013–2016) were significantly larger than that in early periods (e.g., 1998–2012). We conclude that the site was more and more affected by regional sources along with the time. Northern India was possibly becoming the strongest source area to WLG rather than city regions before. The case study in the Tibetan Plateau showed that the atmospheric CH4 observed in Qinghai-Tibetan Plateau changed not as expected, the annual growth rate was even larger than that in city regions in some period (e.g., 7.3 ± 0.1 ppb yr−1 in 2013–2016). It is unambiguous that the anomalously fluctuations of atmospheric CH4 in this region are a warning to the world, its increasingly annual growth rate may be a dangerous signal to global climate change.

The research of greenhouse gases on the Tibetan Plateau is of great importance since its unique topography as the third pole of our planet and profound response on the climate change. In this study, we compared the concurrent observations of atmospheric carbon dioxide (CO2), methane (CH4), and carbon monoxide (CO) during 2010–2016 from two stations located on the Tibetan Plateau, which are Mt. Waliguan station (WLG), the only World Meteorological Organization/Global Atmosphere Watch global station in the inland of Eurasia, and Shangri‐La station, a Chinese national station (XGLL). Although both stations are located at remote area, the atmospheric CO2, CH4, and CO concentrations are frequently influenced by regional sources, especially for XGLL throughout the year and WLG in summer. Due to the unique topography and regional conditions, the atmospheric CH4 and CO at both stations display different trends with other sites in China, with higher values in summer. The atmospheric CO2, CH4, and CO at the XGLL mainly represent the conditions in regional scale. As the only World Meteorological Organization/Global Atmosphere Watch global station in the inland of Eurasia, the observation results at WLG can be used to represent the conditions on the Tibetan Plateau, but some of them are frequently influenced by the emissions from the cities located on the east or north east, and some even can be affect by emissions from the Ganges basin in autumn and winter, which should be treated with caution. By subtracting the influences of the cities, we updated the growth rate of 2.45 ± 0.02 ppm yr−1 for CO2, 8.2 ± 0.1 ppb yr−1 for CH4, and −0.4 ± 0.1 ppb yr−1 for CO, compared to the prior estimation of 2.31 ± 0.02 ppm yr−1 for CO2, 8.1 ± 0.1 ppb yr−1 for CH4, and −0.6 ± 0.1 ppb yr−1 for CO on the Tibetan Plateau.

Low-temperature storage is widely used to maintain the quality of postharvest fruit and prolong the shelf-life. Although the biochemical and physiological changes occurring during pear during storage have been explored in previous studies, the underlying mechanisms remain unclear. Herein, protein expression profiles of pears during cold storage were investigated by two-dimensional electrophoresis (2-DE). Proteomic analysis revealed 22 significantly differentially expressed proteins, 21 of which were identified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). Functional annotation of the differentially expressed proteins (DEP) revealed that many were involved in carbohydrate and energy metabolism, signal transduction and transcriptional regulation, stress response and antioxidants, and protein metabolism. An increase in the activity of ethylene synthesis-related enzymes and a decrease in protein synthesis capacity indicate that fruit senescence remained normal during cold storage. Two pathogenesis-related proteins (β-1,3-glucanase and Pyr c1) in the glycosyl hydrolyse pathway were up-regulated, which may increase the resistance of pears to low temperature or pathogen stress. Our results presented some useful information on the changes of protein during senescence of fragrant pear that will help to better understand cellular events in pears during cold storage, and minimize postharvest losses.

Ice-temperature storage is a new refrigeration method with temperatures ranging from sub-zero to the freezing point of the product being stored. However, few reports have evaluated the effects of ice-temperature (IT) storage on the cell wall metabolism and reactive oxygen metabolism of Xinjiang-grown Diaogan apricots. In this study, to determine the effects of ice-temperature storage on cell wall metabolism and reactive oxygen metabolism in Diaogan apricots, apricots were stored at −1.5 °C to−2.0 °C (ice temperature, IT), 0 °C–1 °C (low temperature), and 10 °C (control) for 70 d with sampling and evaluation every 10 d. Compared to storage at low temperature and 10 °C, IT storage (1) better maintained the firmness, ascorbic acid content, pectin content, and cellulose content of the fruit; (2) suppressed the activities of polygalacturonase and cellulase; (3) inhibited the rate of weight loss, respiration rate, ethylene production, plasma membrane permeability, and malondialdehyde accumulation; and (4) improved the activities of peroxidase, catalase, superoxide dismutase, and ascorbate peroxidase, thereby inhibiting the accumulation of hydrogen peroxide and superoxide anion during storage. Overall, the results show that IT storage is an effective way to improve the storage quality and antioxidant capacity of Diaogan apricots.

The oleaginous yeast Rhodosporidium toruloides AS 2.1389 is viewed as desirable industrial microorganisms that can accumulate a high content of lipids for biodiesel production. In this study, we attempted to improve lipid accumulation in the yeast Rhodosporidium toruloides by UV irradiation mutagenesis and selection based on lithium chloride tolerance or ethanol–H(2)O(2) tolerance. The biomass concentration, lipid yield and glucose consumption of mutant R. toruloides were determined. The transcription levels of lipid accumulation‐related genes in the wild‐type and mutant strains were also determined. The lithium chloride‐tolerant strain R‐ZL2 and the ethanol–H(2)O(2)‐resistant strain R‐ZY13 were generated by UV mutagenesis. The two mutant strains showed greater lipid productivity and lipid yield compared to the wild type. Transcriptional analysis revealed that IDP1, GPD1 and GND were expressed at significantly higher levels in the two high‐lipid‐producing mutants. In conclusion, lipid productivity and lipid yield in R. toruloides were successfully improved via UV mutagenesis and selection. We also identified some lipid accumulation‐related genes for improving lipid productivity through genetic engineering.

Based on attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and principal component analysis (PCA), four kinds of asphalt (two kinds of matrix asphalts, TPC70# and JL70# and two kinds of modified asphalts, SBS-1 and SBS-2) were aged using the rolling thin-film oven test (RTFOT). The multiple stress repeated creep recovery test (MSCR) was carried out on an AR1500ex dynamic shear rheometer (DSR). The PCA was carried out on the attenuated total reflection infrared spectrum of a pretreated aged asphalt, the principal component factors (oxidation factor and component change factor) were determined, the comprehensive index F was calculated, and a prediction model of aging time history was established and verified. A prediction model for the aging asphalt recovery rate R was established based on the functional group index. The relationship between the recovery rate R and aging time history of each aging asphalt was analyzed and the fatigue life of each aging asphalt based on the rate of dissipated energy change (RDEC) was compared. The correlation between the comprehensive index F and fatigue life of asphalt was also analyzed. The results show that the order of resistance to the high-temperature deformation of each aging asphalt is as follows: SBS-2 &gt, SBS-1 &gt, TPC70# &gt, JL70#, the prediction model of aging asphalt recovery rate R based on functional group index has good reliability. Taking the loading cycle corresponding to the sudden increase of the inflection point of the curve, i.e., the fatigue life NRDEC, as the evaluation index, the fatigue life order of each aging asphalt is SBS-1 &gt, SBS-2 &gt, JL70# &gt, TPC70#. There is a positive correlation between the fatigue life of aged asphalt and the comprehensive index F of asphalt. The correlation degree R2 is 0.85, i.e., with the increase of the comprehensive index F of asphalt, its fatigue life also increases. It was found that it is feasible to analyze the aging time history and fatigue life of asphalt by infrared spectroscopy, and it can provide a rapid and non-destructive prediction method for the practical engineering application of asphalt.

The purpose of this study was to investigate the effects of 1-methylcyclopropene (1-MCP) and chitosan treatment on the storage of Xinjiang jujube fruit at 0 ± 1 °C (relative humidity 90 %–95 %) for 42 d. Indicators such as rotting rate, firmness, and soluble solids as well as peroxidase (POD), polyphenol oxidase (PPO), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities were measured. The results showed that 1-MCP or chitosan treatment alone inhibits rotting, delays the decline of soluble solids, maintains fruit firmness, and inhibits the accumulation of malondialdehyde. Furthermore, the activities of antioxidant enzymes such as POD, SOD, CAT, and APX are increased, while those of PPO and LOX are inhibited. However, the effect of 1-MCP and chitosan together is superior to that of 1-MCP or chitosan treatment alone. In conclusion, our results indicate that combined 1-MCP and chitosan treatment is an effective strategy for improving the postharvest quality and prolonging the shelf life of Xinjiang jujube fruit.

In order to achieve the goal of increasing the mileage of pure electric vehicles, a pure electric vehicle was used as the research object, and the parameters of the battery pack were designed and matched, formulate the energy management control strategy based on threshold value, simulate the continuous driving distance of the vehicle with the help of ADVISOR simulation software, under the premise of not affecting the power of pure electric vehicles, the optimal threshold of energy management strategy that effectively increases the driving range of the vehicle is obtained, that is the battery pack's the state of charge is more than 45% and less than 50%, indicate that the energy management control strategy is correct and feasible.

The “double low-points” anomaly in daily variation of vertical geomagnetic component was observed on May 9, 2008 at 13 geomagnetic observatories belonging to the geomagnetic observatory network center of China Earthquake Administration. These observatories distribute roughly on three belts with the intersection in western Sichuan. On May 12, three days after the anomaly appearance, the great MS8.0 Wenchuan earthquake occurred. The “double low-points” anomaly in daily variation of vertical geomagnetic component is an anomalous phenomenon of regional geomagnetism, which does exist objectively. The possible cause is the change of extrinsic eddy current system resulting in geomagnetic daily quiet variation (Sq), or the delay of several hours between the intrinsic and the extrinsic eddy current systems. The relationship between the “double low-points” anomaly of daily geomagnetic variation and the earthquake reveals that the former possibly reflects the accelerative alteration of earthquake gestation in the deep Earth.