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The theory of water evaporation in soil and the soil-water characteristic curve are the core of unsaturated soil research, and have very important guiding significance for engineering practice. This paper uses the theoretical summary method to summarize the theory of water evaporation in soil and the related theory of soil-water characteristic curve. The results show that the water evaporation in the soil is the result of the combined action of internal factors and external factors. Matrix suction is the core of the soil-water characteristic curve. There are many factors that affect the soil-water characteristic curve. The mineral composition and pore structure of soil are the two most essential influencing factors, and other influencing factors mainly play their role through these two factors.

We built a molecular-level kinetic model for hydrocarbon catalytic cracking, incorporating the catalyst acidity as the parameter to estimate the reaction rates. The n-decane and 1-hexene co-conversion catalytic cracking process was chosen as the studying case. The reaction network was automatically generated with a computer-aided algorithm. A modified linear free energy relationship was proposed to estimate the activation energy in a complex reaction system. The kinetic parameters were initially regressed from the experimental data under various reaction conditions. On this basis, the product composition was evaluated for three catalytic cracking catalysts with different Si/Al. The Bronsted acid and Lewis acid as the key catalyst properties were correlated with the kinetic parameters. The built model can calculate the product distribution, and molecular composition at different reaction conditions for different catalysts. The sensitive study shows that it will facilitate the model-based optimization of catalysts and reaction conditions according to product demands.

A grapevine cell line, where actin filaments are labelled by GFP, was used to show that aluminium causes actin remodeling through activation of a NADPH oxidase in the plasma membrane, followed by activation of phytoalexin synthesis genes. Elimination of actin filaments by Latrunculin B disrupts the gene activation, inhibition of MAPK signalling by the inhibitor PD98059 as well. Interestingly, aluminum also induces transcripts for ISOCHORISMATE SYNTHASE, as well as of PR1, which are known to be responsive to salicylic acid. However, aluminium-triggered defence is not as SA responses accompanied by cell death. Also in grapevine leaf discs from two genotypes contrasting in stilbene inducibility, aluminum can induce accumulation of a central grapevine phytoalexins, the stilbene aglycone trans-resveratrol, preceded by a rapid induction of transcripts for RESVERATROL SYNTHASE and the regulating transcription factor MYB14. The amplitude of this induction reflects the general stilbene inducibility of these genotypes, indicating that the aluminum effect is not caused by unspecific toxicity, but by activation of specific signalling. The findings show that, actin filaments activate a specific branch of defence signalling acting in concert with calcium-dependent PAMP triggered immunity. This pathway links apoplastic oxidative burst through MAPK signalling with the activation of defence-related transcripts.

Asparagine synthetase (ASN) and glutamine synthetase (GS) play important roles in nitrogen metabolism and recycling in plants. In this study, we performed the characterization and expression analysis of the ASN and GS gene families in grape. It contains two ASN genes, VviASN1 and VviASN2, and five GS genes, VviGS1.1, VviGS1.2, VviGS1.3, VviGS2a and VviGS2b. For each gene, full-length complementary DNAs were cloned and the properties of encoded protein were predicted using bioinformatics approaches. Real-time PCR analysis showed that the transcript levels of VviASN1, VviASN2, VviGS1.1, VviGS1.2 and VviGS2b during ovule (seed) development were higher in seedless cultivars than in seeded. It was showed that asparagine (Asn) content in the seeds of seedless grapes was higher than in seeded, while glutamine (Gln) content was higher in seeded. Levels of both amino acids increased during early seed development, then decreased as development progressed. Based on correlation between amino acid content and gene expression, VviASN1 may play a major role in the synthesis of Asn in grape seeds. VviASN1 and VviASN2 were highly expressed in flower and leaf, respectively. VviGS1.1, VviGS2a and VviGS2b were highly expressed in leaf, while VviGS1.2 was highly expressed in root. In summary, our findings suggest novel roles for the VviASN and VviGS genes families during seed development/abortion in grapevine.

Many plant cells retain their totipotency when cultured in vitro. The regulation of shoot regeneration from in vitro culture involves a number of gene products, but the nature of the associated post-transcriptional events remains largely unknown. Here, the post-transcriptional regulator ARGONAUTE10 (AGO10), a protein which is specifically expressed in the explant during the period when pro-shoot apical meristems (SAMs) are forming, has been known to inhibit shoot regeneration. In in vitro cultured explants of the loss-of-function mutant ago10, a much larger than normal number of SAMs was formed and, in these, the stem cell marker genes WUSCHEL, CLAVATA3 and SHOOT MERISTEMLESS were all strongly expressed. AGO10 repressed the accumulation of the microRNAs miR165/166, thereby up-regulating a suite of HD-ZIP III genes. The overproduction of miR166 was shown to promote shoot regeneration, while the absence of miR165/166 message resulted in a blockage to shoot regeneration and only a partial rescue of the phenotype of the ago10 mutant. The major conclusion was that the shoot regeneration inhibition determined by AGO10 functions via the repression of miR165/166.

The grapevine VvβVPE promoter is specifically expressed in the seed. The − 1306~− 1045 bp core region restricts expression in other tissues and organs. Vacuolar processing enzyme (VPE) is a cysteine proteinase regulating vacuolar protein maturation and executing programmed cell death (PCD) in plants. Vitis vinifera (Vv)βVPE is a β-type VPE showing seed-specific expression that processes seed proteins during ovule development. However, the regulation of the seed-specific gene expression is far from understood. In this study, we characterize VvβVPE promoter (pVvβVPE) from 12 seeded and seedless grape genotypes. 94.56% of the pVvβVPE coding sequence is consistent. Two βVPE promoters were constructed and transformed into Arabidopsis thaliana via β-glucuronidase (GUS) fused expression vectors, using cv. Pinot Noir and cv. Thompson as seed and seedless candidates. GUS staining in different tissues and organs revealed that VvβVPE expresses specifically in the embryo, including the cotyledon, hypocotyl and suspensor, but not in the leaf, stem, root or flowers of the seedling. Using promoter deletion analysis, we created four incomplete VvβVPE promoters and found each pVvβVPE deletion could drive GUS gene to express in seeds. Interestingly, seed specificity disappeared when the promoter missed the core − 1306~− 1045 bp region. All deletion promoters presenting various quantified GUS activities indicate that the region − 1704~− 1306 bp inhibits, and the region − 705~− 861 bp promotes gene expression of VvβVPE. Our results demonstrate that pVvβVPE is a seed-specific promoter in both seeded and seedless grapes. Moreover, the core region of pVvβVPE (− 1306~− 1045 bp) is the key one responsible for seed-specific expression.

Nanosheet ZSM-5 zeolite with highly exposed (010) crystal planes demonstrates high reactivity and good anti-coking stability for the catalytic cracking of n-heptane, which is attributed to the synergy of high external surface area and acid sites, fully accessible channel intersection acid sites, and hierarchical porosity caused by the unique morphology.

To meet the requirement of gasoline new standard, a concept process for head-tail co-conversion of the longer chain n-alkanes (C10-C12) and olefins (C5 -C7 ) with similar C-C bonding energy in FCC gasoline was developed to reduce olefin content and T50 of gasoline simultaneously. Here 1-hexene and n-decane were chosen as head-tail model compounds of these olefin and n-alkane components in FCC gasoline. By analyzing the product distribution of co-feeding and single-feeding of n-decane and 1-hexene at different reaction temperatures, higher yield of gasoline with lower T50 and higher content of i-paraffin could be obtained through co-feeding process at 325 °C. Besides, the olefin content of gasoline could be successfully decreased. Based on chemical kinetic analysis, it could be found that by co-conversion of n-decane and 1-hexene, the cracking path of 1-hexene was restrained and the formation of i-paraffin was enhanced due to the hydrogen transfer of n-decane with carbocation converted from 1-hexene.

MYB transcription factors are involved in many biological processes, including metabolism, development and responses to biotic and abiotic stresses. RADIALIS-LIKE SANT/MYB 1 (RSM1) belongs to a MYB-related subfamily, and previous transcriptome analysis suggests that RSM1 may play roles in plant development, stress responses and plant hormone signaling. However, the molecular mechanisms of RSM1 action in response to abiotic stresses remain obscure. We show that down-regulation or up-regulation of RSM1 expression alters the sensitivity of seed germination and cotyledon greening to abscisic acid (ABA), NaCl and mannitol in Arabidopsis. The expression of RSM1 is dynamically regulated by ABA and NaCl. Transcription factors ELONGATED HYPOCOTYL 5 (HY5) and HY5 HOMOLOG (HYH) regulate RSM1 expression via binding to the RSM1 promoter. Genetic analyses reveal that RSM1 mediates multiple functions of HY5 in responses of seed germination, post-germination development to ABA and abiotic stresses, and seedling tolerance to salinity. Pull-down and BiFC assays show that RSM1 interacts with HY5/HYH in vitro and in vivo. RSM1 and HY5/HYH may function as a regulatory module in responses to ABA and abiotic stresses. RSM1 binds to the promoter of ABA INSENSITIVE 5 (ABI5), thereby regulating its expression, while RSM1 interaction also stimulates HY5 binding to the ABI5 promoter. However, no evidence was found in the dual-luciferase transient expression assay to support that RSM enhances the activation of ABI5 expression by HY. In summary, HY5/HYH and RSM1 may converge on the ABI5 promoter and independently or somehow dependently regulate ABI5 expression and ABI5-downstream ABA and abiotic stress-responsive genes, thereby improving the adaption of plants to the environment., Author summary The phytohormone abscisic acid (ABA) regulates multiple developmental processes in plants, including seed dormancy and germination, growth, and abiotic stress responses. The transcription factor ELONGATED HYPOCOTYL 5 (HY5), a core regulator of light signaling, is involved in ABA and abiotic stress responses by directly regulating the expression of ABA INSENSITIVE 5 (ABI5). In this study, we show that a MYB-related transcription factor, RADIALIS-LIKE SANT/MYB 1 (RSM1), plays important roles in ABA and salinity signaling in Arabidopsis, and we dissect the relationship between RSM1 and HY5. RSM1 interacts with HY5/HYH in vitro and in vivo and they may function as a regulatory module in responses to ABA and abiotic stresses. RSM1 binds to the promoter of ABI5, thereby regulating its expression; moreover, RSM1 interaction stimulates HY5 binding to the ABI5 promoter, but RSM1 was not found to enhance the activation of ABI5 expression by HY5. Genetic analyses reveal that RSM1 mediates the functions of HY5 in responses of seed germination, post-germination developmental responses to ABA and abiotic stresses, and seedling tolerance to salinity. In summary, our work demonstrates that HY5/HYH and RSM1 may bind with the ABI5 promoter to regulate ABI5 expression independently or somehow dependently, thereby controlling the expression of ABI5-downstream target genes in ABA and salinity signaling.

In this study, the dehydrogenation component of Ga2O3 was introduced into ZSM-5 nanocrystals to prepare Ga2O3/ZSM-5 hollow fiber-based bifunctional catalysts. The physicochemical features of as-prepared catalysts were characterized by means of XRD, BET, SEM, STEM, NH3-TPD, etc., and their performances for the catalytic conversion of n-butane to produce light olefins and aromatics were investigated. The results indicated that a very small amount of gallium can cause a marked enhancement in the catalytic activity of ZSM-5 because of the synergistic effect of the dehydrogenation and aromatization properties of Ga2O3 and the cracking function of ZSM-5. Compared with Ga2O3/ZSM-5 nanoparticles, the unique hierarchical macro-meso-microporosity of the as-prepared hollow fibers can effectively enlarge the bifunctionality by enhancing the accessibility of active sites and the diffusion. Consequently, Ga2O3/ZSM-5 hollow fibers show excellent catalytic conversion of n-butane, with the highest yield of light olefins plus aromatics at 600 °C by 87.6%, which is 56.3%, 24.6%, and 13.3% higher than that of ZSM-5, ZSM-5 zeolite fibers, and Ga2O3/ZSM-5, respectively.

Vacuolar processing enzymes (VPEs) have received considerable attention due to their caspase-1-like activity and ability to regulate programmed cell death (PCD), which plays an essential role in the development of stenospermocarpic seedless grapes ovules. To characterize VPEs and the relationship between stenospermocarpic grapes and the VPE gene family, we identified 3 Vitis vinifera VPE genes (VvβVPE, VvγVPE, and VvδVPE) from the PN40024 grape genome and cloned the full-length complementary DNAs (cDNAs) from the ‘Vitis vinifera cv. Pinot Noir’ and ‘Vitis vinifera cv. Thompson Seedless’ varietals. Each of the VPEs contained a typical catalytic dyad [His (177), Cys (219)] and substrate binding pocket [Arg (112), Arg (389), Ser (395)], except that Ser (395) in the VvγVPE protein sequence was replaced with alanine. Phylogenetic analysis of 4 Arabidopsis thaliana and 6 Vitis vinifera VPEs revealed that the 10 VPEs form 3 major branches. Furthermore, the 6 grapevine VPEs share a similar gene structure, with 9 exons and 8 introns. The 6 grapevine VPEs are located on 3 different chromosomes. We also tested the enzymatic activity of recombinant VPEs expressed in the Pichia Pastoris expression system and found that the VvVPEs exhibit cysteine peptidase activity. Tissue-specific expression analysis showed that VvδVPE is only expressed in flowers, buds and ovules, that VvγVPE is expressed in various tissues, and that VvβVPE was expressed in roots, flowers, buds and ovules. The results of quantitative real-time PCR (qRT-PCR) suggested that VvβVPE in seeded grapes increased significantly at 30 days after full-bloom (DAF), close to the timing of endosperm abortion at 32 DAF. These results suggested that VvβVPE is related to ovule abortion in seedless grapes. Our experiments provide a new perspective for understanding the mechanism of stenospermocarpic seedlessness and represent a useful reference for the further study of VPEs.

CuO nanocrystals with different shapes, i.e.?irregular nanoparticles, nanobelts and nanoplatelets, have been synthesized by controlling a few critical synthesis parameters to explore their catalytic properties. It was found that the rate of CO oxidation on the nanoplatelets is over six times higher than that on the nanoparticles and about three times higher than that on the nanobelts at 110??C. Based on combined characterizations, such as BET, XRD, TEM, HRTEM and CO temperature-programmed reduction, the relationship between the catalytic reactivity and the shape as well as the predominantly exposed crystal planes of the CuO nanocrystals has been discussed.

The effects of calcination atmosphere of the Ag/TS-1 catalyst and other Ti-containing supports on propylene epoxidation using oxygen as the oxidant in a fixed-bed quartz reactor were investigated. The samples were characterized by XRD, UV–vis, ESR, TEM and FT-IR. The results show that 2 wt.% Ag/TS-1 calcined in air is optimum; the Ag/Ti-containing (prepared by chemical vapor deposition (CVD) or impregnation (IMP) method) catalysts have catalytic activities in the reaction. The framework titanium species plays an important role, while the extra framework titanium species (280–290 nm) also has weak epoxidation activity in the gas-phase epoxidation of propylene; excessive extra framework titanium species (280–290 nm) can decrease PO selectivity. The oxidized silver ions are the main active sites for the gas-phase epoxidation of propylene.

The effects of preparation method and precipitator on the catalytic properties of Ag/TS-1 in the gas-phase epoxidation of propylene were investigated in a fixed bed, quartz reactor. The Ag/TS-1 catalysts were characterized by XRD, UV–vis, FT-IR and TEM. The results show that the catalysts prepared by both deposition-precipitation (DP) and impregnation (IMP) methods exhibit catalytic activity and selectivity in the reaction. 0.48% propylene conversion with 57.88% selectivity to PO is obtained over Ag/TS-1 catalyst prepared by IMP method. However, DP method is optimum. Alkaline metal carbonate is a suitable precipitator. Using K 2 CO 3 as the precipitator, the catalyst exhibits high activity and selectivity; using Cs 2 CO 3 as the precipitator, the stability of the catalyst is improved; the propylene conversion and the selectivity to PO are 1.28% and 84.12%, 1.11% and 85.41% at 31 and 54 min, respectively. Besides the dispersion of silver particles, pH value of precipitators as well as the interaction between silver species and the support are the key factors for the gas-phase epoxidation of propylene.

Ag/TS-1 was prepared by microemulsion method in which dioctyl sulfosuccinate sodium salt (AOT) was used as the surfactant and n-heptane as the organic solvent. The synthesized Ag/TS-1 was characterized by UV–Vis and TEM and its catalytic properties in gas-phase propylene epoxidation were carried out in a fixed bed reactor. The results show that Ag is highly dispersed on TS-1 and the crystal size can be adjusted through the adjusting of the molar ratio of water to surfactant ([H2O]/[surfactant] = R). The catalyst prepared with R = 4.74 exhibits the highest catalytic activity for propylene epoxidation in gas-phase, the optimal reaction temperature scope is between 363 and 383 K. Over the catalyst prepared with R = 4.11, propylene conversion and the selectivity to propylene oxide (PO) are 1.1% and 91.0%, respectively.

The effects of preparation conditions, treatment methods of the Ag/TS-1 catalyst and the reaction conditions on propylene epoxidation using oxygen as the oxidant in a fixed-bed quartz reactor were investigated. The catalysts were characterized by XRD, UV-Vis, TEM and ESR spectra. Results show that hydrogen is essential for the epoxidation reaction. The optimum preparation conditions are as follows: Ag loading 2 wt.%, the ratio of Si/Ti in TS-1 64, and calcination temperature (in air) 450 °C. The optimum Ag/TS-1 catalyst, by passing a reactant mixture of C 3 H 6 , O 2 , H 2 and N 2 at 150 °C at a volume ratio of 1:2:3:12 with a space velocity of 4000 h −1 , can exhibit the best results. At this condition, after 70 min reaction the conversion of propylene and the selectivity to propylene oxide are 1.37 and 93.51%, respectively. The results of the characterization show that the oxidized Ag species without single electrons plays an important role in the epoxidation of propylene.

Epoxidation of propylene to propylene oxide over Ag/TS-1 in the presence of oxygen and hydrogen was carried out in a fixed-bed, quartz flow reactor. The effects of Ag loading, Si/Ti ratio of TS-1 and calcination temperature and calcination method of Ag/TS-1 on the propylene epoxidation were investigated. The results show that Ag loading, the calcination temperature and calcination method of Ag/TS-1 as well as the Si/Ti ratio of TS-1 have a great effect on the catalytic properties. The optimum Ag loading, calcination temperature and calcination method of Ag/TS-1 and Si/Ti ratio of TS-1 are 2 wt%, 450 °C in air and 64 respectively. Over 2.0 wt% Ag/TS-1(nSi/nTi = 64) catalyst, at a space velocity of 3000 h-1, 0.92% propylene conversion with 91.21% selectivity to propylene oxide is obtained at 150 °C. The deactivation of Ag/TS-1 catalyst is not due to the changes of active species, but because of the coke of the catalyst, which can be easily regenerated by calcination at 450 °C in air.

Epoxidation of propylene to propylene oxide over Ag/TS-1 in the presence of oxygen and hydrogen was carried out in a fixed-bed, quartz flow reactor. The effects of Ag loading, support, Si/Ti mol ratio of TS-1 and calcination temperature of Ag/TS-1 on the propylene epoxidation were investigated. The results show that Ag loading, support and the calcination temperature of Ag/TS-1 as well as the Si/Ti mol ratio of TS-1 have a great effect on the catalytic properties. The optimum Ag loading, calcination temperature of Ag/TS-1 and Si/Ti mol ratio of TS-1 are 2wt%, 450°C and 64, respectively. Over 2.0wt%Ag/TS-l (n Si /n Ti =64) catalyst, at a space velocity of 300011 1 , 0.92% propylene conversion with 91.2% selectivity to propylene oxide is obtained at 150°C. The deactivation of Ag/TS-1 catalyst is not due to the changes of active species, but the coke of the catalyst, which can be easily regenerated by calcination at 450°C in air.