可持续发展驱动重工业变革

<正>多年来,重工业因高能耗、高污染,一直在可持续发展方面备受诟病。但事实也不完全如此。许多领先的重工业企业,尤其在公用事业、石油天然气和矿产领域,已开始重视可持续发展,并将其融入企业的日常运营当中。在全球各地,重工业企业需要获得比一般法规遵从更为严格的"运营许可",这不仅是法规的问题,也成为推动重工业可持续发展的首要动力。近年来发生的石油、采矿及核事故也说明了这一特殊     

A Novel Technology for Natural Gas Conversion by Means of Integrated Oxidative Coupling and Dry Reforming of Methane

A novel process concept for the oxidative coupling of methane followed by the oligomerization to liquids has been developed within the frame of the EU integrated project OCMOL. This technology is based on process intensification principles via cutting‐edge structured microreactor technology. It is also a fully integrated industrial process through the re‐use and the recycling of by‐products, in particular CO₂, at every process stage. The focus of this contribution is on the reaction engineering aspects of the core steps, i.e., catalysts, kinetics and reactor design for the methane coupling and reforming.     

Interface engineering of nanoceramic hematite photoelectrode for solar energy conversion

This work addresses the role of different modifiers on the overall photocurrent response, which allowed a dual material insertion, increasing the charge separation without compromise the surface catalysis. Sn-addition onto nanoceramic hematite photoelectrodes clearly increased flat band potential, promoting a good charge separation, and shifting the onset to a higher potential, attributed to the surface-trapping state created by this modification. Notoriously, Sn-hematite photoelectrodes loaded with NiFeO_x exhibited the highest photocurrent density, suggesting a partially recovered surface-trapping states created during the electrode designing. The well-known cocatalyst acted in the overall photoelectrocatalytic response with no significant effect on the turn-on voltage, in other words, with minor effect related to catalytic efficiency. The dual modification contributes to understand the role of different modifiers allowing to satisfactorily improve charge separation while maintaining the conductivity attributed to IV-group ions.     

Carborane-Containing Matrix Metalloprotease (MMP) Ligands as Candidates for Boron Neutron-Capture Therapy (BNCT)

Based on the previously reported potent and selective sulfone hydroxamate inhibitors SC-76276, SC-78080 (SD-2590), and SC-77964, potent MMP inhibitors have been designed and synthesized to append a boron-rich carborane cluster by employing click chemistry to target tumor cells that are known to upregulate gelatinases. Docking against MMP-2 suggests binding involving the hydroxamate zinc-binding group, key H-bonds by the sulfone moiety with the peptide backbone residues Leu82 and Leu83, and a hydrophobic interaction with the deep P1’ pocket. The more potent of the two triazole regioisomers exhibits an IC₅₀ of 3.7 nM versus MMP-2 and IC₅₀ of 46 nM versus MMP-9.     

α-Substituierte Phosphonate. 40. 1-Trimethylammonium-1-diethylphosphono-1-cyanomethylid,ein stabiles N-Ylid

α-Substituted Phosphonates. 40. 1-Trimethylammonium-1-diethylphosphono-1-cyanomethylid, a Stable N-Ylid Diethyl-1-dimethylamino-1-cyanomethanephosphonate 4 can be alkylated on nitrogen to the quarternary ammoniumsalts 5 , which by C-deprotonation gives the stable N-ylid 8 . The N-ylid 8 behaves inert against carbonyl compounds and acylating agents, but can be C-alkylated and — involving an ester-dealkylation — C-chlorinated.     

α-Substituierte Phosphonate. 39. Methandiphosphonsäureester durch UV-induzierte Michaelis-Becker-Reaktion

α-Substituted Phosphonates. 39. Methane-diphosphonic Esters by U.V.-Induced Michaelis-Becker-Reaction Dibromomethane resp. chlorbromomethane reacts with sodium dialkyl phosphite in heptane-/liq.NH₃ or in liq. NH₃ by u.v. irradiation at low temperatures to give in good yields methane diphosphonic acid tetraalkylesters 1 . In the same manner with sodium diethyl thionophosphite the corresponding methane-bis-thiophosphonic acid tetraethylester 4 is obtained.     

Hyperketonemia during lipopolysaccharide-induced mastitis affects systemic and local intramammary metabolism in dairy cows

Hyperketonemia interferes with the metabolic regulation in dairy cows. It is assumed that metabolic and endocrine changes during hyperketonemia also affect metabolic adaptations during inflammatory processes. We therefore studied systemic and local intramammary effects of elevated plasma β-hydroxybutyrate (BHBA) before and during the response to an intramammary lipopolysaccharide (LPS) challenge. Thirteen dairy cows received intravenously either a Na-dl-β-OH-butyrate infusion (n = 5) to achieve a constant plasma BHBA concentration (1.7 ± 0.1 mmol/L), with adjustments of the infusion rates made based on immediate measurements of plasma BHBA every 15 min, or an infusion with a 0.9% NaCl solution (control; n = 8) for 56 h. Infusions started at 0900 h on d 1 and continued until 1700 h 2 d later. Two udder quarters were challenged with 200 μg of Escherichia coli LPS and 2 udder quarters were treated with 0.9% saline solution as control quarters at 48 h after the start of infusion. Blood samples were taken at 1 wk and 2 h before the start of infusions as reference samples and hourly during the infusion. Mammary gland biopsies were taken 1 wk before, and 48 and 56 h (8 h after LPS challenge) after the start of infusions. The mRNA abundance of key factors related to BHBA and fatty acid metabolism, and glucose transporters was determined in mammary tissue biopsies. Blood samples were analyzed for plasma glucose, BHBA, nonesterified fatty acid, urea, insulin, glucagon, and cortisol concentrations. Differences were not different for effects of BHBA infusion on the mRNA abundance of any of the measured target genes in the mammary gland before LPS challenge. Intramammary LPS challenge increased plasma glucose, cortisol, glucagon, and insulin concentrations in both groups but increases in plasma glucose and glucagon concentration were less pronounced in the Na-dl-β-OH-butyrate infusion group than in controls. In response to LPS challenge, plasma BHBA concentration decreased in controls and decreased also slightly in the BHBA-infused animals because the BHBA concentration could not be fully maintained despite a rapid increase in BHBA infusion rate. The change in mRNA abundance of citrate synthase in LPS quarters was significant between the 2 treatment groups. The results indicate that elevated circulating BHBA concentration inhibits gluconeogenesis before and during immune response to LPS challenge, likely because BHBA can replace glucose as an energy source.     

Consequences of dietary energy source and energy level on energy balance,lactogenic hormones,and lactation curve characteristics of cows after a short or omitted dry period

Omitting the dry period (DP) generally reduces milk production in the subsequent lactation. The aim of this study was to evaluate the effect of dietary energy source—glucogenic (G) or lipogenic (L)—and energy level—standard (std) or low—on milk production; energy balance (EB); lactogenic hormones insulin, insulin-like growth factor 1 (IGF-1), and growth hormone (GH); and lactation curve characteristics between wk 1 and 44 postpartum in cows after a 0-d or 30-d DP. Cows (n = 110) were assigned randomly to 3 transition treatments: a 30-d DP with a standard energy level required for expected milk yield [30-d DP(std)], a 0-d DP with the same energy level as cows with a 30-d DP [0-d DP(std)], and a 0-d DP with a low energy level [0-d DP(low)]. In wk 1 to 7, cows were fed the same basal ration but the level of concentrate increased to 6.7 kg/d for cows fed the low energy level and to 8.5 kg/d for cows fed the standard energy level in wk 4. From wk 8 postpartum onward, cows received a G ration (mainly consisting of corn silage and grass silage) or an L ration (mainly consisting of grass silage and sugar beet pulp) with the same energy level contrast (low or std) as in early lactation. Cows fed the G ration had greater milk, lactose, and protein yields, lower milk fat percentage, greater dry matter and energy intakes, and greater plasma IGF-1 concentration compared with cows fed the L ration. Dietary energy source did not affect EB or lactation curve characteristics. In cows with a 0-d DP, the reduced energy level decreased energy intake, EB, and weekly body weight gain, but did not affect milk production or lactation curve characteristics. A 30-d DP resulted in a greater total predicted lactation yield, initial milk yield after calving, peak milk yield, energy intake, energy output in milk, days to conception [only when compared with 0-d DP(low)], plasma GH concentration [only when compared with 0-d DP(std)], and decreased weekly body weight gain compared with a 0-d DP. A 30-d DP decreased both the increasing and the declining slope parameters of the lactation curve and the relative rate of decline in milk yield (indicating greater lactation persistency) compared with a 0-d DP, and decreased plasma insulin and IGF-1 concentration, and EB. In conclusion, feeding a G ration after wk 7 in milk improved energy intake and milk production, but did not affect EB compared with an L ration. For cows without a DP, a reduced dietary energy level did not affect milk production and lactation curve characteristics, but did decrease EB and weekly body weight gain. A 30-d DP increased milk yield and lactation persistency, but decreased milk fat and protein content, EB, and plasma insulin and IGF-1, compared with a 0-d DP.     

Using chromium stable isotope ratios to quantify Cr(VI) reduction: lack of sorption effects

Chromium stable isotope values can be effectively used to monitor reduction of Cr(VI) in natural waters. We investigate effects of sorption during transport of Cr(VI) which may also shift Cr isotopes values, complicating efforts to quantify reduction. This study shows that Cr stable isotope fractionation caused by sorption is negligible. Equilibrium fractionation of Cr stable isotopes between dissolved Cr(VI) and Cr(VI) adsorbed onto gamma-Al2O3 and goethite is less than 0.04 per thousand (53Cr/52Cr) under environmentally relevant pH conditions. Batch experiments at pH 4.0 and pH 6.0 were conducted in series to sequentially magnify small isotope fractionations. A simple transport model suggests that adsorption may cause amplification of a small isotope fractionation along extreme fringes of a plume, leading to shifts in 53Cr/52Cr values. We therefore suggest that isotope values at extreme fringes of Cr plumes be critically evaluated for sorption effects. A kinetic effect was observed in experiments with goethite at pH 4 where apparently lighter isotopes diffuse into goethite clumps at a faster rate before eventually reaching equilibrium. This observed kinetic effect may be important in a natural system that has not attained equilibrium and is in need of further study. Cr isotope fractionation caused by speciation of Cr(VI) between HCrO4- and CrO4(2-) was also examined, and we conclude that it is not measurable. In the absence of isotope fractionation caused by equilibrium speciation and sorption, most of the variation in delta53Cr values may be attributed to reduction, and reliable estimates of Cr reduction can be made.     

Photoreduction of Shewanella oneidensis Extracellular Cytochromes by Organic Chromophores and Dye‐Sensitized TiO2

The transfer of photoenergized electrons from extracellular photosensitizers across a bacterial cell envelope to drive intracellular chemical transformations represents an attractive way to harness nature's catalytic machinery for solar‐assisted chemical synthesis. In Shewanella oneidensis MR‐1 (MR‐1), trans‐outer‐membrane electron transfer is performed by the extracellular cytochromes MtrC and OmcA acting together with the outer‐membrane‐spanning porin ? cytochrome complex (MtrAB). Here we demonstrate photoreduction of solutions of MtrC, OmcA, and the MtrCAB complex by soluble photosensitizers: namely, eosin Y, fluorescein, proflavine, flavin, and adenine dinucleotide, as well as by riboflavin and flavin mononucleotide, two compounds secreted by MR‐1. We show photoreduction of MtrC and OmcA adsorbed on Ru^II‐dye‐sensitized TiO₂ nanoparticles and that these protein‐coated particles perform photocatalytic reduction of solutions of MtrC, OmcA, and MtrCAB. These findings provide a framework for informed development of strategies for using the outer‐membrane‐associated cytochromes of MR‐1 for solar‐driven microbial synthesis in natural and engineered bacteria.