首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
After the experimentation for more thanone year and the production of 200000mflax textiles,the project for the applicationof biological enzyme in flax dyeing and fin-ishing jointly undertaken by ShenzhenXinlong Flax Textile Bleaching and Dye-ing Co.,Ltd.and Tsinghua University hasrecently passed experts'appraisal.Expertsthink that the technology is well developedand suitable for large-scale production and  相似文献   

2.
A distillery industry which represents an important segment of the world economy is amongst the highly polluting industries after the paper industries. Spent wash (SW) generated from distilleries have a very high chemical oxygen demand (COD) (i.e., 20,000–50,000 mg/dm3) and biological oxygen demand (BOD) (i.e., 7000–50,000 mg/dm3), while the COD and BOD values depend on the raw material used. If it is discharged to water-receiving bodies without treatment, it may damage the aquatic system. Apart from causing water pollution, unpleasant odor of effluent spreads several kilometers around the distillery. The untreated/partially treated effluent if discharged in the land makes it infertile. Environmental issues have become one of the important factors controlling the growth of distillery industries. Therefore, it is very necessary to investigate the efficient and cost-effective processes to treat SW. The physicochemical processes are still not being applied in many distilleries, which are possible to have feasible remediation technologies to combat environmental pollution. In the present review article, different physicochemical technologies like coagulation, flocculation, electrocoagulation, thermolysis, wet oxidation, and adsorption as well as biological treatment for the wastewater of distillery industries have been presented. The distillery wastewater management is also discussed.  相似文献   

3.
The dominant theory in the field of mammalian herbivore–plant interactions is that intake, and therefore tolerance, of plant secondary metabolites (PSMs) is regulated by mechanisms that reduce absorption and increase detoxification of PSMs. Methods designed by pharmacologists to measure detoxification enzyme activity, metabolite excretion, and most recently, drug absorption, have been successfully applied by ecologists to study PSM intake in a variety of mammalian study systems. Here, we describe several pharmacological and molecular techniques used to investigate the fate of drugs in human that have potential to further advance knowledge of mammalian herbivore–plant interactions.  相似文献   

4.
2,4-Thiazolidinedione (TZD) is a privileged and highly utilised scaffold for the development of pharmaceutically active compounds. This sulfur-containing heterocycle is a versatile pharmacophore that confers a diverse range of pharmacological activities. TZD has been shown to exhibit biological action towards a vast range of targets interesting to medicinal chemists. In this review, we attempt to provide insight into both the historical conventional and the use of novel methodologies to synthesise the TZD core framework. Further to this, synthetic procedures utilised to substitute the TZD molecule at the activated methylene C5 and N3 position are reviewed. Finally, research into developing clinical agents, which act as modulators of peroxisome proliferator-activated receptors gamma (PPARγ), protein tyrosine phosphatase 1B (PTP1B) and aldose reductase 2 (ALR2), are discussed. These are the three most targeted receptors for the treatment of diabetes mellitus (DM).  相似文献   

5.
《分离科学与技术》2012,47(7):1505-1520
Abstract

Fenton‐and Fenton‐like AOPs systems have been utilized for the oxidative degradation of some chlorinated pollutants such as chloral hydrate or 1,1,1‐trichloroethane, and for the treatment of real industrial wastewaters. Both ferrous sulfate (FeSO4 · 7 H2O) and Mohr's salt (NH4)2Fe(SO4)2. 6 H2O have been used as Fe2+ ion sources. With Mohr's salt (MS) the Fenton‐and Fenton‐like reaction has been successfully carried out under acidic (pH 3) and neutral (pH 7) reaction conditions. The new Fenton‐like system utilizes zero‐valent iron (Feo) instead of ferrous sulfate has been applied for the 1,1,1‐trichloroethane and chloral hydrate degradation. Similarly, the application of catechol‐ and hydroquinone‐driven Fenton reaction for the degradation of chloral hydrate under acidic and neutral pH is a new Fenton‐like AOPs approach. The photo‐Fenton‐like reactions such as Fe3+/hν, Fe2+/H2O2/hν, and ferrioxalate system have been also studied for the degradation of chloral hydrate. As an irradiation source a daily light or sun light have been used. In comparison with photoreactor experiments the best system was observed to be Fe3+/hν. In some experiments the influence of standing time prolongation after Fenton reaction on the final degradation efficiency due to hydrolysis of intermediates such as phosgene (CCl2?O) has also been studied. The Fenton reaction was successfully utilized for the treatment of real industrial wastewaters, in two cases even in plant‐scale applications.  相似文献   

6.
Plant allelopathy offers hope as an additional means of weed control in modern agriculture. Its mechanisms and molecular basis are not yet well understood. Research on the chemical basis for allelopathy has often been hindered by the complexity of plant and soil matrices, making it difficult to track active compounds. Recent improvements in the cost and capabilities of bench-top chromatography–mass spectrometry instruments make these tools more powerful and more widely available to assist with molecular studies conducted in today's expanding field. Such instrumental techniques are herein recommended as economically efficient means of advancing the rigor of allelopathy research and assisting the development of a better understanding of the chemical basis for the allelopathy phenomenon.  相似文献   

7.
ABSTRACT

An analysis of desorption isotherms for potato shows the following probable qualities in the water-potato system. In the natural state the water is bound rather strongly due to loss of rotational degrees of freedom in the sorbed molecules, which is caused by small molecular voids in the cellulose structure. This structure therefore is formed as a uniformly cross bound state of the OH-groups. This state prevails up to a certain temperature, above which a reaction sets in, where OH bonds are successively broken, giving possibility for a partial rotation of sorbed molecules. In the range of lower moisture content the cellulose structure is changed into a crystalline state as in wood, although the degree of crystallinity is lower, which is the probable reason why the statistical fluctuations in the isotherms are greater for potato than for wood.  相似文献   

8.
Heterogeneous catalysis is inherently a complex subject, and progress toward making it a science rather than an art has required knowledge and techniques in many fields. In recent times physical tools such as electron microscopy and optical and magnetic resonance spectroscopy have seen increasing use and have yielded many interesting new results. This paper is a discussion of Mössbauer spectroscopy, a tool capable of giving new information concerning catalysis. In the first half we review the physical parameters which play a role in the Mössbauer effect and discuss briefly the techniques used in its measurement (the general references for this section are [1] and [2]). In the last half we discuss applications of the effect to studies of adsorption and catalysis with examples from the literature and our own exploratory work.  相似文献   

9.
In this paper the influences of preozonation on the effectiveness of NOM adsorption and biodegradation processes are studied. Three different types of water have been used in this study: A natural water from the Úzquiza Reservoir (Burgos, Spain), synthetics waters prepared using natural humic substances (fulvic and humic acids extracted from the Úzquiza Reservoir) and a synthetic water prepared using a commercially supplied humic acid. The effect of preozonation on NOM adsorption by activated carbon is evaluated: adsorption of humic acids (hydrophobic, high molecular weight compounds) is improved following preozonation; however, for the fulvic acids (hydrophilic, low molecular weight compounds), no net appreciable effect of preozonation on adsorption was observed. Preozonation increases the biodegradability of NOM: biodegradable dissolved organic carbon (BDOC), which was determined using two different bioassays (Billen-Servais method and Joret-Lévi method), increases with increasing ozone dosage. A characterization of humic substances based on their adsorption and biodegradability properties is also reported, showing the effect of ozone.  相似文献   

10.
Nicotiana attenuata plants growing in close proximity to damaged sagebrush (Artemisia tridentata ssp. tridentata) suffer less herbivory than plants near undamaged sagebrush. Sagebrush constitutively releases methyl jasmonate (MeJA), a compound that when applied directly to N. attenuata, elicits herbivore resistance and the direct defense traits [protease inhibitors (PIs), nicotine]. Damage increases the release of volatile MeJA, primarily in the cis epimer, suggesting that cis-MeJA may mediate this apparent interplant signaling. We characterized sagebrush's MeJA plume before and after damage in nature and in the laboratory, and compared the activity of trans- and cis-MeJA in inducing PIs, nicotine, and Manduca sexta resistance in N. attenuata. We used both lanolin applications and aqueous sprays that mimic natural exposures, and we determined the amount of volatilized MeJA required to elicit a nicotine response in open-grown plants. Wounding rapidly and transiently increased cis-MeJA emissions from damaged parts (but not systemically), and the released plume did not rapidly dissipate in nature. cis-MeJA was not consistently more active than trans-MeJA, and the order of exposure (trans- then cis-) did not influence activity. We conclude that volatile MeJA, either trans- or cis-, when applied at levels consistent with those released by sagebrush does not elicit direct defenses in N. attenuata.  相似文献   

11.
Trafficking of soluble cargo to the vacuole is far from being a closed issue as it can occur by different routes and involve different intermediates. The textbook view of proteins being sorted at the post-Golgi level to the lytic vacuole via the pre-vacuole or to the protein storage vacuole mediated by dense vesicles is now challenged as novel routes are being disclosed and vacuoles with intermediate characteristics described. The identification of Vacuolar Sorting Determinants is a key signature to understand protein trafficking to the vacuole. Despite the long established vacuolar signals, some others have been described in the last few years, with different properties that can be specific for some cells or some types of vacuoles. There are also reports of proteins having two different vacuolar signals and their significance is questionable: a way to increase the efficiency of the sorting or different sorting depending on the protein roles in a specific context? Along came the idea of differential vacuolar sorting, suggesting a possible specialization of the trafficking pathways according to the type of cell and specific needs. In this review, we show the recent advances in the field and focus on different aspects of protein trafficking to the vacuoles.  相似文献   

12.
In this article the influence of preozonation on the effectiveness of NOM removal via coagulation processes will be studied (focusing on the influence of the calcium hardness) as well as changes in MW (molecular weight) distribution of humic substances caused by ozonation. Additionally, THMFP removal in both ozonation and preozonation-coagulation processes is assessed. Three different types of water have been used in this study: a natural water from the Úzquiza Reservoir (Burgos, Spain), a synthetic water prepared using natural fulvic acids extracted from the Úzquiza Reservoir and a synthetic water prepared using a commercially supplied humic acid. Molecular weights of humic substances were determined using high-performance size exclusion chromatography (HPSEC); average molecular weights calculated for the unozonated humic substances are 4500 Da for the commercial humic acids and 1000 Da for the natural fulvic acids extracted from the Úzquiza Reservoir. Preozonation shifted the molecular weight distribution of humic substances (both humic and fulvic acids) towards lower average molecular weight values. For the natural water from the Úzquiza Reservoir (with low levels of calcium hardness and hydrophobic fraction (humic substances) being the main fraction of NOM), preozonation has a negative effect on the effectiveness of the coagulation process for NOM removal: the percentages of TOC removal via coagulation decrease with increasing ozone dosage; the maximum TOC removal (33%) is achieved for the unozonated water. Also for this water, ozonation reduced 5–25% of THMFP with ozone doses varying from 0.25 to 2.5 mg O3/L. A preferential THMFP removal, that is to say, higher reduction in THMFP (43%) relative to TOC (28%) is achieved by the coagulation-flocculation process; this also occurs when preozonation is used, independently of ozone dosage.  相似文献   

13.
PAH (Polycyclic Aromatic Hydrocarbons) analyses were carried out on samples from two Wastewater Treatment Plants (WWTPs) in Lombardy, similar for treatment sequences but fed on different influents: industrial component accounts for 70% at Alto Seveso plant while it is absent in Nosedo plant. Sampling concerned the influent and the effluent from activated sludge reactor and the final effluent after disinfection (ozonation for Alto Seveso and peracetic acid treatment for Nosedo). The concentrations of total PAHs were 5.3 ± 4.0 μg L?1 and 2.4 ± 1.3 μg L?1 in Alto Seveso and Nosedo influent, respectively. The lowest molecular weight PAHs had the highest concentrations in both plants; acenaphthene and naphthalene were the most important components in the influent to Alto Seveso and Nosedo WWTPs, respectively. The higher molecular weight compounds had the lowest concentrations and benzo(g,h,i)perylene and dibenzo(a,h)anthracene were never detected. Most of the PAH load entered biological treatment in dissolved form. For both plants PAHs were mostly removed in the biological section (96.5% and 89.5% for Alto Seveso and Nosedo, respectively), while disinfection had a minor role. Peracetic acid (Nosedo) seemed more efficient than ozone (Alto Seveso) in the removal of PAHs (4.18% and 0.89%, respectively). It is now necessary to confirm this result by using the same effluent for the two disinfection treatments.  相似文献   

14.
Effluent from the Pa?aköy Wastewater Treatment Plant was oxidized by using O3 and O3/H2O2. DOC, COD, UV254, total coliform, dissolved ozone and some endocrine disrupting compounds were monitored during oxidation. Results showed that O3 provided superior disinfection, however, lower reductions in DOC, COD and endocrine disrupting compounds were exhibited compared to O3/H2O2. The highest removal efficiency of DOC, COD and endocrine disrupting compounds were achieved at 0.5 molar ratio of O3/H2O2. The benefit of H2O2 addition for advanced oxidation reduced significantly when the mole ratio was increased to 2. Therefore, the mole ratio of H2O2 to O3 is a critical parameter for the design of wastewater oxidation by O3/H2O2.  相似文献   

15.
Pancreatic Ductal Adenocarcinoma (PDAC) constitutes a leading cause of cancer death globally. Its mortality remains unaltered despite the considerable scientific progress made in the fields of diagnostics and treatment. Exosomes comprise of small extracellular vesicles secreted by nearly all cells; their cargo contains a vast array of biomolecules, such as proteins and microRNAs. It is currently established that their role as messengers is central to a plethora of both physiologic and pathologic processes. Accumulating data have shed light on their contributions to carcinogenesis, metastasis, and immunological response. Meanwhile, the advancement of personalized targeted therapies into everyday clinical practice necessitates the development of cost-efficient treatment approaches. The role of exosomes is currently being extensively investigated towards this direction. This review aims to summarize the current pre-clinical and clinical evidence regarding the effects of exosomal applications in the timely diagnosis, prognosis, and therapeutic management of pancreatic cancer.  相似文献   

16.
Journal of Inorganic and Organometallic Polymers and Materials - Metal–organic frameworks (MOFs) provide advantages as supporting materials for the immobilization of enzymes due to their...  相似文献   

17.
Catalytic wet air oxidation (CWAO) was investigated in laboratory-scale experiments for the treatment of o-chlorophenol in wastewater. Experimental results showed that wet air oxidation (WAO) process in the absence of catalyst was also effective for o-chlorophenol in wastewater treatment. Up to 80% of the initial CODcr was removed by wet air oxidation at 270℃ with twice amount of the required stoichiometric oxygen supply. At temperature of 150℃, the removal rate of CODCr was only 30%. Fe2(SO4)3, CuSO4, Cu(NO3)2 and MnSO4 exhibited high catalytic activity. Higher removal rate of CODcr was obtained by CWAO. More than 96% of the initial CODcr was removed at 270℃ and 84.6%-93.6% of the initial COD Cr was removed at 150℃. Mixed catalysts had better catalytic activity for the degradation of o-chlorophenol in wastewater.  相似文献   

18.
The microstructure and slag erosion fractal dimension of reaction interface of β-Sialon-Al2O3 brick used in 300 Mt iron ladle of Baosteel have been studied by SEM and XRD.The results indicated that β-Sialon-Al2O3 brick exhibited excellent slag resistance.The main wear mechanism of β-Sialon-Al2O3 brick is mainly from the spalling caused by thermal mechanical stress and attacked by slag secondly.  相似文献   

19.
ABSTRACT

An analysis of desarption isotherms for potato shows the following probable qualities in the water-potato sysarn. in the natural staa the walcr is bound rather strongly due to loss of rotational degrees of freedom in the sorbed molecules, which is caused by small molecular voids in the cellulose structure. This strucmre therefore is formcd as a uniformly cross bound state of the OH-groups. This slate prevails up to a cenin temperature, above which a reaction sas in. whcre OH bonds are successively braken, giving passibility for a panial rotation of sorbed molecules. in the range of lower moisture conlcnt the cellulose strucmre is changed into n crystalline slate a in wood, although the dcgrcc of crystallinity is lower, which is thc  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号