The Impact of Energy Management Control Systems on Energy Efficiency in the German Manufacturing Industry

Although previous studies point to much (untapped) potential for energy efficiency enhancement in industry, empirical research that adapts findings of environmental control to the context of energy management remains widely neglected. Specifically, previous environmental research suggests that the implementation of energy management control systems (EnMCS) could be an effective lever for companies to enhance their production systems and operations toward energy efficiency. Yet, empirical evidence for this theoretical proposition is rather missing; thus, debate continues regarding whether the high investments to set up a comprehensive EnMCS pay off in the long run. Based on a sample of 236 German manufacturing companies, this study combines primary data that capture the configuration of EnMCS with secondary data that were used to calculate energy efficiency. The results provide evidence that the extent of EnMCS implementation positively relates to firms’ energy efficiency. Findings from additional moderation analysis suggest that companies might enhance the relationship of EnMCS and energy efficiency performance by establishing a full‐time energy manager or by using external energy consulting support.     

Improvement of both lipid and biomass productivities of Qatar Chlorocystis isolate for biodiesel production and food security

Microalgae are considered a very promising alternative for biofuel production. Several strategies were developed to modulate and improve algae metabolites production to meet the requirements for biodiesel production. Most previous research evidenced that the increase of the lipid content is accompanied by a decrease of the biomass production, which increases the cost of the downstream processing. Hence, the challenge is to find special culture conditions that increase the lipid and the biomass productivities simultaneously. In the present work, we developed a strategy for the improvement of biomass and lipid productivities in a novel local microalga isolate, Chlorocystis sp. QUCCCM14, which was not previously known as a promising strain. Indeed, culturing QUCCCM14 using f/2 medium with 10× NaH₂PO₄ (0.15 g L^?1 NaNO₃ and 5.6 mg L^?1 NaH₂PO₄) resulted in an improvement of 3.178 folds the lipid productivity reaching 56.121 mg L^?1 day^?1 and enhanced the biomass productivity reaching 141.363 mg L^?1 day^?1, simultaneously. Comparative analyses of the FAME profiles demonstrated that fed‐batch culture with phosphate or nitrate separately leads to a high production of the omega 3 fatty acids (Linolenic acid), whereas fed‐batch culture with phosphate and nitrate simultaneously increased the production of fatty acids suitable for biodiesel production.     

Old and new glycopeptide antibiotics: From product to gene and back in the post-genomic era

Glycopeptide antibiotics are drugs of last resort for treating severe infections caused by multi-drug resistant Gram-positive pathogens. First-generation glycopeptides (vancomycin and teicoplanin) are produced by soil-dwelling actinomycetes. Second-generation glycopeptides (dalbavancin, oritavancin, and telavancin) are semi-synthetic derivatives of the progenitor natural products. Herein, we cover past and present biotechnological approaches for searching for and producing old and new glycopeptide antibiotics. We review the strategies adopted to increase microbial production (from classical strain improvement to rational genetic engineering), and the recent progress in genome mining, chemoenzymatic derivatization, and combinatorial biosynthesis for expanding glycopeptide chemical diversity and tackling the never-ceasing evolution of antibiotic resistance.     

Improving the Shear Strength of Quartz Sand using the Microbial Method

An increase in urban population and the reduced number of suitable lands for construction projects have necessitated the need for ground improvement methods with no environmentally detrimental effects. Microbial-induced calcite precipitation (MICP) is a relatively environmentally friendly method for soil regeneration. In the present paper, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed to investigate the type and method of cement formation in loose quartz sand with different densities stabilized using bacteria. The results showed that the highest content of calcium carbonate cement was produced in the sample with the lowest density. Moreover, after microbial stabilization, the shear strength measured in the direct shear test was increased in the specimen with a lower density. We observed an increase in shear strength from 0.63 kg/cm² before injection for loose sand (γ = 1.5 g/cm³) to 3.92 kg/cm² after injection. In addition, the effect of injection time was investigated and found that shear strength in the two-stage injection per day is greater than that in one- and three-stage injections per day. With prolonging the injection time from one to five days, shear strength was significantly increased from 2.07 to 4.54 kg/cm². Furthermore, prolonging the bacterial treatment period led to a significant increase in the produced carbonate cement and, consequently, enhanced soil shear strength.     

Impact of Oxygen Availability on Microbially Induced Calcite Precipitation (MICP) Treatment

Most microbially induced calcite precipitation (MICP) processes are induced by aerobic bacteria; thus, oxygen availability plays an important role in MICP treatment. To determine the effects of oxygen supply on MICP treatment catalyzed by Sporosarcina pasteurii, contrast tests under an aerated condition, air-restricted condition, and open air condition were conducted. The results showed that dissolved oxygen (DO) in the air-restricted reactor decreased with time and was almost exhausted within 7 days; DO in the open box decreased by 50% after 7 days of treatment because of the superficial air supply; and DO in the aerated box maintained an initial high level because the consumed oxygen was supplied immediately by adequate air bubbles in the treatment solution. Unconfined compressive strength (UCS) and CaCO₃ content are high under the aerated condition, moderate under the open condition, and poor under the air-restricted condition. The UCS can be 100 times different depending on the different oxygen supply conditions. The overall influence process is as follows: oxygen is dissolved to supply DO for life and activity of the aerobic urea hydrolysis bacteria; then, urea is hydrolyzed to carbonate anions for CaCO₃ precipitation in the presence of Ca²⁺; and finally, CaCO₃ precipitation results in the strengthening of sand. The results indicate that a sufficient air supply is essential to improve MICP processes catalyzed by aerobic bacteria.     

植物甜蛋白的研究进展

本文简要介绍了近年来在植物中发现的几种甜味蛋白质的分子结构及其化学性质。讨论了它们在结构上的相关性及可能的甜味机制,并对甜蛋白在食品工业及植物改良方面的应用进行了展望。     

Medium improvement by orthogonal array designs for cholesterol oxidase production by Rhodococcus equi No. 23

Medium improvement for the production of cholesterol oxidase (CO, EC 1.1.3.6) by Rhodococcus equi No. 23 was investigated using an orthogonal array design in two steps. Results revealed that yeast extract, Tween 80 and zinc sulphate had positive effects on CO production, but magnesium sulphate had an inhibitory effect. In addition, interaction between cholesterol and sodium chloride also had a significant effect on enzyme production. The improved medium consisted of 2·0 g/litre cholesterol, 8·0 g/litre yeast extract, 1·0 g/litre NH₄Cl, 1·0 g/litre NaCl, 0·50 g/litre KH₂PO₄, 0·25 g/litre Na₂HPO₄, 0·10 g/litre -valine, 0·15 g/litre -tyrosine, 0·15 g/litre MgSO₄·7H₂O, 0·01 g/litre ZnSO₄·7H₂O, 0·10 g/litre FeSO₄·7H₂O and 4·0 ml/litre Tween 80. CO production at 60 h (about 0·24 units/ml) was about four-fold greater than with the control medium.     

Genetic Diversity of a Tropical Tree Species,Shorea leprosula Miq. (Dipterocarpaceae), in Malaysia: Implications for Conservation of Genetic Resources and Tree Improvement1

Genetic diversity and population genetic structure of Shorea leprosula was investigated using seven natural populations distributed throughout Peninsular Malaysia and one natural population from Borneo. The mean population and species level genetic diversity were exceptionally high (H_e= 0.369 ± 0.025 and 0.406 ± 0.070, respectively). Heterozygosity varied among populations, ranging from 0.326 to 0.400, with the highest values found in the populations from central Peninsular Malaysia. Correlations among ecological factors (longitude, latitude, and annual rainfall) were not significant (P > 0.05), indicating that these ecological variables were not responsible for the observed genetic differences among populations. The Bangi adult population exhibited a higher level of observed heterozygosity but lower fixation indices in comparison to its seedling population. All other seedling populations also showed positive fixation indices (f), indicating a general excess of homozygotes. This also may suggest selection against homozygotes between the seedling and adult stages. A low level of population differentiation was detected (G_ST= 0.117 with the Lambir population and GST= 0.085 without the Lambir population). Furthermore, gene flow (N_m) between populations was not significantly correlated with geographical distances for the populations within Peninsular Malaysia. Cluster analysis also did not reflect geographical proximity and gave little insight into the genetic relatedness of the populations. This may indicate that the populations sampled are part of a continuous population with fragmentation having occurred in the recent past.     

不同有机废弃物改良新复垦耕地的综合效果评价

由废弃地整理复垦形成的耕地存在土壤有机质和有效养分低、土壤板结、微生物活性弱和土壤耕作性状不良等问题,快速、有效地提高土壤肥力质量是全面提升该类耕地质量和生产性能的重要组成部分.本文通过田间小区试验研究了城郊有机废弃物对新复垦耕地土壤培肥的综合效果,并比较了不同类型城郊有机废弃物在培育耕地质量方面的差异.试验设置了施用等量猪粪、鸡粪、水稻秸秆、蔬菜收获残留物、城市污泥、沼渣、猪粪/水稻秸秆堆肥、生活垃圾堆肥和对照（不施有机肥）9个处理（年用量30 t·hm^-2）,连续进行3年的定点试验.结果表明： 施用任何有机物对改善土壤肥力均有明显的作用.其中,提升土壤碳库管理指数以施用猪粪、鸡粪、猪粪/水稻秸秆堆肥、水稻秸秆和沼渣的效果最为显著;增加土壤水稳定性团聚体和降低土壤容重以施用猪粪/水稻秸秆堆肥和沼渣的效果最佳;施用污泥、猪粪/水稻秸秆堆肥和生活垃圾堆肥可增强土壤保蓄能力;施用猪粪、鸡粪和猪粪/水稻秸秆堆肥对增加土壤有效态养分的效果最为明显;各类有机物均显著提高了土壤微生物数量和酶活性.长期施用污泥、生活垃圾堆肥及畜禽粪存在着土壤重金属污染的风险,但短期施用对土壤环境质量影响不明显.总体上,对土壤肥力的改善效果由大至小依次为：猪粪/水稻秸秆堆肥>鸡粪>猪粪>沼渣>生活垃圾堆肥>水稻秸秆>城市污泥>蔬菜收获残留物;对土壤的相对污染程度由大至小为：城市污泥>生活垃圾堆肥>猪粪>鸡粪>沼渣>猪粪/水稻秸秆堆肥>蔬菜收获残留物>水稻秸秆.     

Intertribal hexaploid somatic hybrid plants regeneration from electrofusion between diploids of Citrus sinensis and its sexually incompatible relative, Clausena lansium

 Chinese wampee [Clausena lansium (Lour.) Skeels], a sexually incompatible relative of citrus, is commercially cultivated in South China. In this study, embryogenic protoplasts of ‘Bonanza’ navel orange [Citrus sinensis (L.) Osbeck] were electrically fused with leaf protoplasts isolated from ‘Chicken Heart’ Chinese wampee. After 8 months of culture, fusion products regenerated into shoots. More than 70% of the shoots unexpectedly rooted well. Chromosome counting of several shoot- and root-tips revealed that their chromosome numbers were not 2n=4x=36 as expected, but 2n=6x=54, suggesting that chromosome doubling occurred rather than chromosome elimination in this intertribal fusion combination. RAPD analysis of embryoids and the leaves of unrooted and rooted shoots verified their hybridity. This is the first report of hexaploid somatic hybrid plant regeneration from fusion between diploids in Aurantioideae. Received: 20 June 1998 / Accepted: 18 August 1998