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The LATERAL ORGAN BOUNDARIES (LOB) DOMAIN/ASYMMETRIC LEAVES2-LIKE (LBD/ASL) gene family members play key roles in diverse aspects of plant development. Previous studies have shown that LBD16, 18, 29 and 33 are critical for integrating the plant hormone auxin to control lateral root development in Arabidopsis thaliana. In the present study, we show that LBD14 is expressed exclusively in the root where it promotes lateral root (LR) emergence. Repression of LBD14 expression by ABA correlates with the inhibitory effects of ABA on LR emergence. Transient gene expression assays with Arabidopsis protoplasts demonstrated that LBD14 is a nuclear-localized transcriptional activator. The knock-down of LBD14 expression by RNA interference (RNAi) resulted in reduced LR formation by delaying both LR primordium development and LR emergence, whereas overexpression of LBD14 in Arabidopsis enhances LR formation. We show that ABA (but not other plant hormones such as auxin, brassinosteroids and cytokinin) specifically down-regulated β-glucuronidase (GUS) expression under the control of the LBD14 promoter in transgenic Arabidopsis during LR development from initiation to emergence and endogenous LBD14 transcript levels in the root. Moreover, RNAi of LBD14 enhanced the LR suppression in response to ABA, whereas LBD14 overexpression did not alter the ABA-mediated suppression of LR formation. Taken together, these results suggest that LBD14 promoting LR formation is one of the critical factors regulated by ABA to inhibit LR growth, contributing to the regulation of the Arabidopsis root system architecture in response to ABA.

Propane dehydrogenation in oxygen free environment over alumina-supported chromium oxide catalysts with different chromium loading was studied within short time-on-stream range for the fluidized moving bed applications. For this purpose, a series of CrOx/Al2O3 and CrOx/Zr-Al2O3 catalysts were prepared and examined. Increase in the chromium loading resulted in reduction of monochromate species, possibly leading to formation of polychromate species. Further increase of chromium loading led to formation of Cr2O3 species. Accordingly, specific activity of the catalyst decreased with increasing chromium loading. Propane conversion significantly decreased and propylene selectivity increased during an induction period due to the rapid consumption of limited lattice oxygen in the catalyst. Equilibrated and artificially-aged catalysts were characterized in order to investigate the factors affecting propylene selectivity and catalyst durability by pore analysis, temperature-programmed reduction (H2-TPR), temperature-programmed desorption (NH3-TPD), X-ray diffraction patterns (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). After an artificial catalyst aging treatment, all catalysts showed reduction in catalytic activity and the most drastic activity decrease was found in the catalyst with the highest loading of 20 wt% Cr/γ-Al2O3 sample. The activity loss was mainly due to agglomeration of the chromium species, reduction of the surface area, and transformation of Cr6+ species into stable Cr2O3 species. Cr species were agglomerated on the surface of alumina support during the aging treatment and the agglomeration was more pronounced at the high Cr loading. Moreover, Raman spectroscopy and XRD analyses revealed the formation of chromia/alumina solid solution in the catalyst after the aging treatment which also significantly contributed to the activity loss. Contrarily, Zr modified alumina support successfully suppressed the formation of chromia/alumina solid solution phase and substantially improved the catalytic activity after the aging treatment by increasing the dispersion of chromium oxide. Zr-Al2O3 support showed lower catalytic activity toward propylene than Al2O3 support, which also contributed to the higher propylene yield of Cr/Zr-Al2O3.

A multi-stage fluidized bed process for CO 2 capture is a novel process for reducing regeneration energy. This process is consist of low-, mid-, and high-temperature stage. Each stage has an absorber and a regenerator. Solid absorbents circulating in these fluidized beds absorb and regenerate CO 2 by temperature swing. PEI-, MgO-, and Li 4 SiO 4 -based absorbents are utilized for low-, mid-, and high-temperature stage. The main feature of this process is a heat recovery scheme; i) an intra-stage heat exchanger, ii) an inter-stage heat exchanger. In the intra-stage heat exchanger, a sensible heat of lean and rich sorbents from regenerator and absorber is exchanged. In the inter-stage heat exchanger, a heat of absorption of mid- and high-temperature stage is supplied to a heat of regeneration of low- and mid-temperature stage. A bench-scale facility that can process 60 Nm 3 /hr flue gas is constructed for conducting a feasibility study of this process. From the experiments of the low-temperature stage, it can capture CO 2 with an efficiency of 80%, however, due to a low efficiency of intra-stage heat exchanger, the regeneration energy and total utility cost are estimated as 4.65 GJ and $36.9 per ton-CO 2 . The three-stage process is evaluated through a process simulation study based on the absorption performance measured at a lab-scale apparatus. The resulted regeneration energy is estimated as 2.37 GJ per ton CO 2 and total utility cost is $39.1 and $24.5 per ton CO 2 in the absence and in the present of steam-turbine, respectively. Finally, a parametric study of the absorption capacity of sorbents and MTA of intra-stage heat exchanger are also been conducted and discussed.

LATERAL ORGAN BOUNDARIES DOMAIN/ASYMMETRIC LEAVES2-LIKEs (hereafter referred to as LBD) are plant-specific transcription factors that play important roles in a plethora of plant growth and development. The leucine (Leu) zipper-like coiled-coil motif in the lateral organ boundaries domain of the class I LBD proteins has been proposed to mediate protein dimerization, but it has not been experimentally assessed yet. LBD16 and LBD18 have been well characterized to play important roles in lateral root development in Arabidopsis (Arabidopsis thaliana). Here, we investigated the role of the coiled-coil motif in the dimerization of LBD16 and LBD18 and in transcriptional regulation and biological function. We built the molecular models of the coiled coil of LBD16 and LBD18, providing the probable Leu zipper models of the helix dimer. Using a variety of molecular techniques, such as bimolecular fluorescence complementation, luciferase complementation imaging, GST pull down, and coimmunoprecipitation assays, we showed that the conserved Leu or valine residues in the coiled-coil motif are critical for the dimerization of LBD16 or LBD18. Using transgenic Arabidopsis plants that overexpress HA:LBD16 or HA:LBD16Q in lbd16 or HA:LBD18 or HA:LBD18Q in lbd18, we demonstrated that the homodimerization of LBD18 mediated by the coiled-coil motif is crucial for transcriptional regulation via promoter binding and for lateral root formation. In addition, we found that the carboxyl-terminal region beyond the coiled-coil motif in LBD18 acts as an additional dimerization domain. These results provide a molecular basis for homodimerization and heterodimerization among the 42 Arabidopsis LBD family members for displaying their biological functions.

We successfully synthesized hydrothermally stable ZSM-5 with crystalline nano seeds. We employed a template-free method using ZSM-5 crystalline nano seeds and sodium silicate as a silica source. The prepared ZSM-5 exhibited uniform crystal size and relative crystallinity greater than 100 %. The size of the crystalline nano seed in the scale of 100 nm was found to be the optimum size for obtaining uniform, highly crystalline ZSM-5 with structural stability. After P-modification, the synthesized ZSM-5 with the optimally sized seed showed high hydrothermal stability and improved catalytic naphtha cracking activity compared to a commercial ZSM-5 catalyst. In order to find the elements for the increased hydrothermal stability, the samples were evaluated by studying crystallinity, aluminum spectrum, and acidity using XRD, solid-state NMR, and NH3-TPD, respectively after steaming at 800 °C for 24 h. It is speculated that the increased hydrothermal stability of the ZSM-5 resulted mainly from the increased aluminum structural stability.

CuO/Al 2 O 3 was used for dehydrogenation of butenes (1-butene, cis-2-butene, and trans-2-butene) to 1,3-butadiene at 200 °C under an anaerobic condition without an excessive amount of dilution. 1,3-butadiene was selectively obtained from butenes without the formation of carbon oxides over the CuO/Al 2 O 3 catalyst. Bifunctionality of oxidation and C−H bond activation by CuO and Al 2 O 3 , respectively, were strongly required for the selective conversion of the butenes to 1,3-butadiene.

The inter-conversion of light olefins over four types of HZSM-5 based catalysts under cracking conditions was investigated systematically and various methods including XRD, Ar adsorption–desorption, NH3-TPD, 27Al and 31P MAS–NMR were used to characterize the effects of P modification and steaming on ZSM-5. Regardless the types of catalyst, the same behaviors of light olefin inter-conversion were observed only depending on conversion of light olefins. Also, the conversion and selectivity were not influenced by the presence of hydrogen, suggesting that light paraffins were mainly produced from hydrogen transfer during cracking rather than hydrogenation of light olefins. It can be suggested that the inter-conversion of light olefins occurs through oligomerization of light olefins and then re-cracking of the oligomerized products. To guarantee high light olefin yield in catalytic naphtha cracking, it is strongly required to suppress oligomerization of light olefins during catalytic cracking.

For the kinetic study of K2CO3/ZrO2 sorbent in the carbonation reaction to capture CO2 from the flue gas, reaction experiments were carried out at temperatures between 328 and 343 K for CO2 gas compositions not exceeding 18% at 1 bar, and a phenomenological kinetic model was proposed to fit the carbonation conversion data obtained. Time-dependent carbonation conversions of the sorbent appeared as sigmoid curves. Sigmoid characteristics of the conversion curve were more pronounced for the sorption reaction at lower temperature and lower gas phase concentration of CO2. Such conversion behavior of fresh-dried K2CO3/ZrO2 sorbent could be closely described with the reaction rate equation in the form: r = kf(X)yCO2n . The reaction rate constant k as a temperature dependent term could be represented by Arrhenius’ equation with the negative apparent activation energy of −17.43 kJ/mol and the pre-exponential factor of 3.83 × 10–3 1/min. The term f(X) was a function introduced to reflect the carbonation rate change...

Hydrogenation of silicon tetrachloride (SiCl 4 ) to trichlorosilane (SiHCl 3 ) using carbon-based catalysts is studied. The results show that surface functional groups that result from the defect sites of the carbon catalysts play an important role in producing SiHCl 3 . Because the metal−carbon composites obtained by treating sucrose and transition metals at high temperature in the N 2 flow have more defect sites, they display an increased SiHCl 3 yield. Elemental analysis of the catalyst and reaction results demonstrate that there is a very good correlation between the SiHCl 3 yield and the amount of deposited silicon during the induction time, and the SiHCl 3 yield and the accumulated amount of deposited Si species rapidly change initially and then reach a stable value. Hydrogenation of SiCl 4 to SiHCl 3 in metal-grade silicon (mg−Si) powder is known to give a higher equilibrium conversion of SiCl 4 . In a similar way, by introducing Si powder into the catalyst bed, a higher SiHCl 3 yield can be obtained. It is important to retard the reverse reaction rate of HCl and SiHCl 3 to increase the SiHCl 3 yield; therefore, the HCl concentration in the product stream should be reduced as soon as it is formed on the catalyst surface during the hydrogenation of SiCl 4 . Consequently, the Si-doped metal−carbon composite catalyst shows a higher SiHCl 3 yield than that of the physically-mixed catalyst and mg−Si powder. These results offer a quite promising potential for developing a stable and effective SiCl 4 hydrogenation catalyst and can promote a deeper understanding of this important poly-Si industry reaction.

Cytokinin signaling in Arabidopsis thaliana utilizes a multi-step two-component signaling (TCS) system comprised of sensor histidine kinases (AHKs), histidine phosphotransfer proteins (AHPs), and response regulators (ARRs). Recent studies have suggested that the cytokinin TCS system is involved in a variety of other signaling and metabolic pathways. To further explore a potential function of the cytokinin TCS in the Arabidopsis dehydration stress response, we investigated the expression of all type-A ARR genes and a type-C ARR, ARR22, in both wild type and ahk single, double, and triple mutants in response to dehydration compared to cytokinin as well as dehydration tolerance of ahk mutants. We found that drought significantly induced the expression of a subset of ARR genes, ARR5, ARR7, ARR15, and ARR22. The results of expression analyses in ahk single, double, and triple mutants demonstrated that the cytokinin receptors AHK2 and AHK3 are redundantly involved in dehydration-inducible expression of ARR7, but not that of ARR5, ARR15, or ARR22. Dehydration tolerance assays showed that ahk2 and ahk3 single mutants exhibited enhanced dehydration tolerance compared with that of wild-type plants and ahk4 mutants, and that ahk2 ahk3 double mutants exhibited stronger drought tolerance than that of ahk3 ahk4, which exhibited more enhanced drought tolerance than that of wild-type plants and ahk single mutants. Taken together, these results demonstrate that while the cytokinin receptors AHK2 and AHK3 are critically involved in the dehydration tolerance response, both cytokinin receptor-dependent pathway and receptor-independent pathway occur in the dehydration response regulating ARR gene expression. In addition, preincubating ahk2, ahk3, ahk4, and the wild-type plants with cytokinin induced enhanced dehydration stress tolerance in these plants, demonstrating that cytokinins are involved in regulating plant response to dehydration stress.

The influences of steaming or washing treatment on P-modified HZSM-5 catalyst were investigated systematically in order for getting deep insight into the role of P species in catalytic cracking. The impregnation of P leads to better hydrothermal stability and higher yields of light olefin (ethylene and propylene), but brings rapid decrease of acidity. During steaming, the impregnated P species become more condensed phase and the acidity and catalytic activity decreased further. However, the acidity and catalytic cracking activity recovered just by washing with water even for steamed samples, suggesting that the existence of condensed P species blocks the pores of zeolite reversibly and are responsible for the decrease of cracking activity of naphtha.

A number of important chemicals are made from light olefins such as propylene and ethylene, and it is expected that market demand for these light olefins will continue to grow at 4–5% annually, and the average overall growth of propylene will be about 1% higher than that of ethylene. From the viewpoint of supply of feedstock and demand of light olefins, it is anticipated that the thermal cracking process of naphtha will be gradually transformed to a catalytic process such as ACOTM that can efficiently produce both ethylene and propylene in high yield. Also, together with primary light olefin production technologies utilizing heavy feedstocks such as DCCTM, and HPFCC, supplementary propylene production technologies utilizing C4–C4 such as SUPERFLEXTM, MOITM, and PROPYLURTM will be applied gradually in commercial production.

Silicon- and Boron-modified H-BEA(Si/Al ratio of 12.5) were prepared by chemical liquid deposition (CLD) of tetraethyl orthosilicate (TEOS) and post-modification method using boric acid, respectively. The catalytic performance of the modified H-BEA catalysts was evaluated for the isomerization of 2,7-dimethyltetralin (DMT) to 2,6-DMT. It was found that the silylation with TEOS passivated preferentially the external acid sites of H-BEA zeolite while the Boron passivated both of the external and internal acid sites. The strong Bronsted acid sites were responsible for the side reactions such as dealkylation, cracking and transalkylation and can be prevented effectively by the silylation and boronation of BEA zeolite.

Summary 1. Heavy alcohol consumption has been known as a risk factor for hypertension, although the mechanism by which alcohol intake causes hypertension remains elusive. 2. We tested the hypothesis that brief exposure to ethanol augments vascular contractility through the stress response in human chorionic plate arteries. 3. Human chorionic plate arteries were mounted in organ baths and exposed to 5% ethanol for 15, 30 or 45 min. 4. Brief exposure for 45 min, but not 15 min, not only augmented contractility to KCl and 5-hydroxytryptamine 5 h after the end of exposure, but also increased the expression of heat shock protein (HSP) 70 in the tissues. 5. Reverse transcription–polymerase chain reaction showed gradual increases of hsp70 mRNA expression, but not heat shock cognate 70 (hsc70), hsp90α or glucose regulatory protein 78 (grp78) mRNA expression, in an exposure time-dependent manner 3 h after the end of exposure. 6. These results indicate that ethanol augments vascular contractility through the stress response.

The developmental process of lateral root formation consists of priming, initiation, primordium development and the emergence of lateral roots from the primary root. Molecular genetic studies with Arabidopsis have revealed several key transcriptional regulators involved in lateral root development. However, their functional interaction has not been fully characterized yet. Here we utilized a genetic approach to understand some of these interactions, revealing that PUCHI functioning in morphogenesis of early lateral root primordium is regulated downstream of ARF7 / ARF19 and acts with LBD16 (ASL18)/ LBD18 (ASL20) to regulate lateral root development. We showed that auxin-responsive expression of PUCHI was significantly reduced in arf7 or arf19 single mutants and completely abolished in arf7 arf19 double mutants. Consistent with this, β-glucuronidase (GUS) expression under the PUCHI promoter in arf7 arf19 was greatly reduced in the lateral root primordium compared with that in the wild type and did not respond to exogenous auxin. Results of GUS expression analyses under the PUCHI , LBD16 or LBD18 promoter in lbd16 , lbd18 single and double mutants or puchi demonstrated that PUCHI and LBD16 or LBD18 do not regulate each other’s expression. Lateral root phenotypes of double and triple mutants of lbd16 , lbd18 and puchi showed that the puchi mutation in lbd16 and lbd18 mutants synergistically decreased the number of emerged lateral roots. These analyses also showed that puchi affected lateral root primordium development of lbd16 or lbd18 additively but differentially. Taken together, these results suggest that PUCHI co-acts with LBD16 and LBD18 to control lateral root primordium development and lateral root emergence.

The gene encoding Schwanniomyces occidentalis alpha-amylase (AMY) was introduced into the chromosomal delta sequences of an industrial strain of Saccharomyces cerevisiae. To obtain a strain suitable for commercial use, an delta-integrative cassette devoid of bacterial DNA sequences was constructed that contains the AMY gene and aureobasidin A resistance gene (AUR1-C) as the selection marker. The AMY gene was expressed under the control of the alcohol dehydrogenase gene promoter (ADC1p). The alpha-amylase activity of Sacc. cerevisiae transformed with this integrative cassette was 6 times higher than that of Sch. occidentalis. The transformants (integrants) were mitotically stable after 100 generations in nonselective medium.