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1.
Germination and biometric parameters (number and length of needles, root length, trunk height, root neck diameter, and fractional seedling mass) of pine (Pinus sylvestris L.) and spruce (Picea abies L. Karst) seedlings with a closed root system are evaluated. The seedlings are grown on a mix of peat with growing media prepared of pulp and paper mill waste (PPW) conversed by worms (Eisenia foctida) using chlorine-free pulp bleaching technology. The growing media includes active sludge; mixes of soil, bark, and woodchip product slivers ground together in a crusher; and coniferous sawdust. The share of (PPW) media is 20, 50 and 100 vol %. The experimental results have shown that in most cases the parameters of pine and spruce seedlings grown on these media in small volumes (20%) reach the parameters of the control samples represented by the seedlings grown on fertilized peat. When a growing medium is used in small amounts, the aboveground/subterraneous ratio of the seedlings is also similar to the control values. The more the growing medium is applied, the lower the parameters of the seedlings are in comparison with the control figures. This is probably caused by the offset of the nitrogen status of the growing media to nitrate nitrogen, which is not typical of natural forest soils.  相似文献   

2.
Arterial oxygen saturation (SaO(2)) was measured at 3,600-3,850 m by pulse oximetry at rest and during submaximal exercise in three study groups: 1) highland Aymara natives of the Bolivian altiplano (n = 25); 2) lowland European/North American sojourners to the highlands with at least 2 months of acclimatization time to 3,600 m (n = 27); and 3) subjects of European ancestry born and raised at 3,600 m (n = 22). Aymara subjects maintained approximately 1 percentage point higher SaO(2) during submaximal work up to 70% of their maximal work capacity, and showed a smaller rate of decline in SaO(2) with increasing work compared to both European study groups. The higher-exercise SaO(2) of Aymara compared to Europeans born and raised at 3,600 m suggests genetic adaptation. The two European study groups, who differed by exposure to high altitude during their growth and development period, did not show any significant difference in either resting or exercise SaO(2). This suggests that the developmental mode of adaptation is less important than the genetic mode of adaptation in determining exercise SaO(2). A weak correlation was detected (across study groups only) between the residual forced vital capacity (FVC) and the residual SaO(2) measured at the highest level of submaximal work output (P = 0.024, R = 0.26). While firm conclusions based on this correlation are problematic, it is suggested that a part of the higher SaO(2) observed in Aymara natives is due to a larger lung volume and pulmonary diffusion capacity for oxygen. Results from this study are compared to similar studies conducted with Tibetan natives, and are interpreted in light of recent quantitative genetic analyses conducted in both the Andes and Himalayas.  相似文献   

3.
Based on feed composition, fish composition and feed conversion, some theoretical effects of feeding on waste discharge are calculated to illustrate the appropriateness of farm effluent monitoring. The effects of feed conversion and feed spillage and feed composition on waste discharge (suspended and dissolved N, P & COD) are demonstrated. Slight variations in feed conversion at the moment of sampling, especially those evoked by feed spillage, have tremendous consequences for discharge values. It appears crucial to determine whether observed conversions are explained by inherent efficiencies of fish growth, or whether higher growth efficiencies are combined with feed spillage. Therefore, thorough knowledge of relationships between nutrient intake and growth should be applied to effluent assessment. A calculation is presented to serve as a preliminary assessment of the impacts of these variables on water quality monitoring. The concept is illustrated using measurements from a recirculation pilot eel culture system.  相似文献   

4.
Hydrolytic ability of laboratory enzyme preparations from fungus of the Penicillium genus was investigated using kraft pulp from nonbleached softwood and bleached hardwood cellulose as substrates. The enzyme preparations were shown to efficiently hydrolyze both softwood and hardwood cellulose. The yields of glucose and reducing sugars were 24–36 g/l and 27–37 g/l from 100 g/l of dry substrate in 48 h, respectively, and depended on the number of substrate grinding cycles.  相似文献   

5.
Two upflow anaerobic hybrid reactors treated lactose and a mixture of ethanol, propionate and butyrate, respectively, at a volumetric loading rate of 3.7 kg chemical oxygen demand (COD) m−3day−1, a hydraulic retention time of 5 days and a liquid upflow velocity of 0.01 m/h. Under steady-state conditions, the lactose-fed sludge had much higher (20%–100%) specific methanogenic conversion rates than the volatile-fatty acid␣(VFA)/ethanol-fed sludge for all substrates tested, including VFA. In both reactors, a flocculant sludge developed, although a much higher content of extracellular polysaccharide was measured in the lactose-fed sludge [1900 μg compared to 305 μg uronic acid/g volatile suspended solids (VSS)]. When the liquid upflow velocity of a third, VFA/ethanol-fed reactor was increased to 0.5 m/h, granulation of the sludge occurred, accompanied by a large increase (200%–500%) in the specific methanogenic conversion rates for the syntrophic and methanogenic substrates studied. Granulation reduced the susceptibility of the sludge to flotation. Glucose was degraded at a high rate (100 mg glucose gVSS−1h−1) by the sludge from the third reactor, despite not having been exposed to a sugar-containing influent for 563␣days. Received: 7 June 1996 / Received revision: 23 September 1996 / Accepted: 29 September 1996  相似文献   

6.
Anaerobic co-digestion of algal sludge and waste paper to produce methane   总被引:6,自引:0,他引:6  
The unbalanced nutrients of algal sludge (low C/N ratio) were regarded as an important limitation factor to anaerobic digestion process. Adding high carbon content of waste paper in algal sludge feedstock to have a balanced C/N ratio was undertaken in this study. The results showed adding 50% (based on volatile solid) of waste paper in algal sludge feedstock increased the methane production rate to 1170+/-75 ml/l day, as compared to 573+/-28 ml/l day of algal sludge digestion alone, both operated at 4 g VS/l day, 35 degrees C and 10 days HRT. The maximum methane production rate of 1607+/-17 ml/l day was observed at a combined 5 g VS/l day loading rate with 60% (VS based) of paper adding in algal sludge feedstock. Results suggested an optimum C/N ratio for co-digestion of algal sludge and waste paper was in the range of 20-25/1.  相似文献   

7.
L(+)-lactic acid production was investigated using an enzymatic hydrolysate of waste office automation (OA) paper in a culture of the filamentous fungus Rhizopus oryzae. In 4 d culture, 82.8 g/l glucose, 7 g/l xylose, and 3.4 g/l cellobiose contained in the hydrolysate were consumed to produce 49.1 g/l of lactic acid. The lactic acid yield and production rate were only 0.59 g/g and 16.3 g/l/d, respectively, only 75% and 61% of the results from the glucose medium. The low production rate from waste OA hydrolysate was elucidated by trials using xylose as the sole carbon source; in those trials, the lactic acid production rate was 7.3 g/l/d, only 28% that of glucose or cellobiose. The low lactic acid yield from waste OA hydrolysate was clarified by trials using artificial hydrolysates comprised of 7:2:1 or 7:1:2 ratios of glucose:cellobiose:xylose. For both, the lactic acid production rate of 17.4 g/l/d matched that of waste OA paper, while the lactic acid yield was similar to that of the glucose medium. This indicates that the production rate may be inhibited by xylose derived from hemicellulose, and the yield may be inhibited by unknown compounds derived from paper pulp.  相似文献   

8.
Summary Soybean waste is a good substrate for biomass production, and the expression of amylolytic, xylanolytic and proteolytic enzymes, by selected mushroom fungi. Considerable potential exists for converting soybean wastes into added-value products using systems based on these fungi.  相似文献   

9.
Dialyzed paper pulp waste liquor added at 20% (v/v) basal medium improved the production of indole alkaloid, catha-ranthine, from Catharanthine roseus, yielding 51 :g/cell as against 42 g/cell in non-supplemented medium. 30-40% (v/v) of catharanthine was secreted out of the cells, showing that the change of the ratio of inner to outer concentrations was from 12.3 to 2.2 at dilution rate of 0.1 h during chemostat cultivation. An optimal dilution rate was 0.34 h in 20% (v/v) supplemented medium, compared to 0.22 h in non-supplemented medium.  相似文献   

10.
Twenty-three purebred Alpine (n=8), Saanen (n=7) and Damascus (n=8) goat bucks raised at the Institute of Reproduction and Artificial Insemination in Thessaloniki, Greece (40 degrees 37 minutes N, 22 degrees 58 minutes E and altitude 32 m above sea level), were used to study the effect of photoperiod on semen production. Samples were collected with an artificial vagina and examined immediately after collection. In spite of the variation in nearly all semen characteristics studied among the 3 breeds of bucks, there was significant seasonal variation in both semen quantity (volume, concentration and total number of spermatozoa per ejaculate) and quality (percentage of motile spermatozoa, percentage of abnormal spermatozoa and rate of progressive motility). The best semen was produced during the breeding season (late summer and autumn). However, the magnitude of these seasonal effects was not sufficient to prevent bucks from being used for breeding throughout the year. Nevertheless, individual differences in the semen quantity and quality among bucks within a breed make individual evaluation of semen necessary to select the most fertile males for breeding.  相似文献   

11.
Summary A filter paper surface cultivation method (previously described as a tool for strain selection by Röhr et al. 1979) was adopted as a cultivation system for citric acid production on a small scale and compared with submerged cultivation. Citric acid production in the submerged system was optimal at defined low concentrations of zinc, ferrous and manganese ions, defined phosphate and nitrogen concentrations and within a defined initial pH. In constrast, citric acid production in the filter paper system was not at all influenced by any of these variables. On the other hand, optimal citrate production in both systems required a high (10%–14%, w/v) sucrose concentration. This identifies sugar concentration as a most significant parameter for citrate production, whereas all other nutritional effects are related to the cultivation system used.  相似文献   

12.
Brewery waste (brewer's grains) was used at four different levels (10%, 20%, 30% and 40% w/w) replacing rice bran in fish diet under a semi-intensive culture system and its impact on the growth of catla, Catla catla; rohu, Labeo rohita and mrigal, Cirrhina mrigala, was studied. Growth in terms of body weight gain was maximum in C. catla and L. rohita fed on a diet containing 30% brewery waste in the feed, whereas C. mrigala, fed on a diet containing brewery waste at the above mentioned levels showed poorer growth than the control. A better growth performance was attributed to better absorption and utilization ability.  相似文献   

13.
The aim of this study was determine whether the introduction of a high-fat diet during the peripubertal phase induces significant changes in body weight control, glucose homeostasis and the parasympathetic tonus compared with the administration of this diet to adult rats. High-fat diet was offered to male Wistar rats at weaning or during adulthood. A group of rats received high-fat diet for 60 days, from weaning to 81-day-old (HF81) or from 60 to 120-day-old (HF120), whereas 2 other groups received a normal-fat diet (i. e., NF81 and NF120). We analyzed adiposity, glucose homeostasis, insulin sensitivity, and vagal nerve activity. High-fat diet increased the accumulation of adipose tissue in all of the rats, but the difference was greater in the rats that were fed the high-fat diet since weaning (p<0.001). The HF rats showed glucose intolerance with high levels of insulin secretion during the glucose tolerance test (p<0.01). Rats that were fed the high-fat diet presented severe insulin resistance, indicated by a low K itt (p<0.01). Interestingly, the HF81 rats exhibited greater insulin resistance compared with the HF120 rats (p<0.05). The recordings of vagus nerve activity showed that the HF rats had higher parasympathetic activity than the NF rats irrespective of age (p<0.01). Our results show that a high-fat diet offered to rats just after weaning or in adulthood both cause impairment of glycemic homeostasis and imbalance in parasympathetic activity. Importantly, the consumption of high-fat diet immediately after weaning has more drastic consequences compared with the consumption of the same diet during adulthood.  相似文献   

14.
An experiment was conducted to study the rumen digestion characteristics of whole feeds (WF) and the neutral detergent fibre (aNDF) and neutral detergent soluble (NDS) fractions of a range of starch-rich feeds using an automated in vitro gas production (GP) technique. In addition, the ruminal digestibility values predicted from the GP data were compared to previously acquired in vivo data. Nine feeds with starch concentrations ranging from 389 to 712 g/kg dry matter and with known in vivo digestibilities were subjected to neutral detergent extraction. The GP for each WF and the corresponding aNDF fractions were measured in duplicate in buffered rumen fluid during 72 h on two occasions. The fermentation residues were collected and analyzed for aNDF concentration to estimate their true organic matter (OM) and NDF digestibility. The GP from the NDS fraction was calculated by subtracting the GP from the aNDF fraction from the GP of the WF. A three-pool Gompertz model was fitted to the GP profiles (R2 = 0.99) and a two compartment, mechanistic and dynamic rumen model was used to predict the digestibility of the potentially digestible feed fraction and the effective digestion rate (kd). The true OM and NDF digestibility determined for the WF ranged from 0.804 to 1.011 and from 0.362 to 1.107, respectively. The NDF digestibility determined for the aNDF fraction ranged from 0.410 to 0.985. The effective kd values estimated using GP data varied from 0.118 to 0.282/h for the WF and from 0.123 to 0.301/h for the NDS fraction, and were less (P<0.05) for maize compared to small grains (SG) but did not differ between barley and wheat (P>0.05). The effective kd values for the aNDF fraction ranged from 0.039 to 0.082/h and did not differ (P>0.05) either between maize and SG or between barley and wheat. The predicted ruminal NDS digestibility determined using GP data closely matched the in vivo data describing starch digestion (R2 = 0.81). The effective kd values for the WF were strongly related (R2 = 0.94) to those for the NDS fractions. The results indicate that when measured with the GP technique, the differences in the digestion characteristics of maize and small grains are less than those previously reported in studies using the in situ method. It is concluded that the predicted NDS digestibility determined using GP data corresponded well to the in vivo starch digestibility. Our results also suggest that the first order digestion rates of NDS (starch) in starch-rich feeds can be accurately determined by incubating WF samples in the GP system and using the GP kinetic data in a dynamic, mechanistic rumen model.  相似文献   

15.
Methylobacterium sp. ZP24 is able to produce poly-3-hydroxybutyrate (PHB) from sucrose and lactose. As the production of PHB is growth-associated, a strategy of intermittent feeding of sugars and other nutrients was assessed for obtaining high yields of the polymer. Higher PHB synthesis was obtained at increased sugar feed rates. Cellular PHB contents of 63% and 71%, with productivities of up to 0.354 and 0.645 g PHB/l h were obtained from sucrose and lactose, respectively. A short-duration semicontinuous production level of up to 2.4 g PHB/l h was achieved in the lactose fermentation. Journal of Industrial Microbiology & Biotechnology (2000) 25, 276–279. Received 06 June 2000/ Accepted in revised form 31 August 2000  相似文献   

16.
The effect of pulp and paper mill waste discharges in the Swale, a tidal channel on the southeast coast of England, has been studied. A pulsing tidal movement in the Swale results in effluent being trapped within the estuary for up to 20 days. This has resulted in adverse effects on the quality of the water and sediment along a substantial part of the estuary with the greatest effect occurring east of the mill in the direction of the residual current. A reduction in the dissolved oxygen concentration occurred along a 13-km stretch of the estuary with mean values falling to 53 % saturation near the mill. High levels of organic matter in the sediment reflect the deposition of material from the mill effluent stream and loss on ignition values of up to 12 % were found east of the mill, falling to 5 % within 4 km northwest of the mill. The macrofauna of the intertidal mudflats was typical of a stressed environment with a low number of species and with a few being represented by large numbers of individuals. The dominant species was the sabellid polychaeteManayunkia aestuarina which reached peak numbers of over 1.5 million m−2, 1.5 km east of the mill. An increase in the total biomass near the mill is thought to be associated with organic enrichment from the mill wastes.  相似文献   

17.
Anaerobic digestion of animal waste is a technically viable process for the abatement of adverse environmental impacts caused by animal wastes; however, widespread acceptance has been plagued by poor economics. This situation is dismal if the technology is adapted for treating low strength animal slurries because of large digester-volume requirements and a corresponding high energy input. A possible technology to address these constraints is the anaerobic sequencing batch reactor (ASBR). The ASBR technology has demonstrated remarkable potential to improve the economics of treating dilute animal waste effluents. This paper presents preliminary data on the effects of temperature and frequency-cycle on the operation of an ASBR at a fixed hydraulic retention time (HRT). The results suggest that within the parameter range under consideration, temperature did not affect the biogas yield significantly, however, higher cycle-frequency had a negative effect. The biogas quality (%CH(4)) was not significantly affected by temperature nor by the cycle-frequency. The operating principle of the ASBR follows four phases: feed, react, settle, and decant in a cyclic mode. To improve the biogas production in an ASBR, one long react-phase was preferable compared to three shorter react-phases. Treatment of dilute manure slurries in an ASBR at 20 degrees C was more effective than at 35 degrees C; similarly more bio-stable effluents were obtained at low cycle-frequency. The treatment of dilute swine slurries in an ASBR at the lower temperature (20 degrees C) and lower cycle-frequency is, therefore, recommended for the bio-stabilization of dilute swine wastewaters. The results also indicate that significantly higher VFA degradation occurred at 20 degrees C than at 35 degrees C, suggesting that the treatment of dilute swine slurries in ASBRs for odor control might be more favorable at the lower than at the higher temperatures examined in this study. Volatile fatty acid reduction at the two reactor temperatures and cycle-frequencies, from a high of 639+/-75 mg/L to a low of 92+/-23 mg/L, greatly reduced the odor and the odor-generation potential in post-treatment storage. The nutrients (both N and P) in the waste influent were conserved in the effluents.  相似文献   

18.
The green flagellate Euglena gracilis has been used as a model organism to elucidate the possible large-scale and short-term effects of waste substances from the pulp and paper industry on photosynthetic efficiency (PE). Different concentrations of waste substances before and after treatment in a cleaning system were studied. The uncleaned sample at concentrations up to 1:10 and the cleaned sample at concentrations up to 1:5 showed stimulating effects on the PE after 7 days of incubation compared to the control. The effects of waste substances on the PE of E. gracilis were also studied in combination with short-term studies (20 and 40 min) of ultraviolet-B radiation (UV-B, 280–320 nm). It was shown that increasing concentrations of the uncleaned sample had continuously stimulating effects on the PE and worked protectively against UV-B radiation. The cleaned sample exhibited no effects, or negative effects, on the PE of E. gracilis together with UV-B radiation compared to the experiments with only UV-B radiation. At the concentration 1:1 of the cleaned sample an increase in the PE was detected due to the high concentration of the coloured substances and a decrease in the UV-B penetration. PE revealed itself to be highly sensitive for detecting toxic effects on E. gracilis and is thus very promising for use in regular toxicity tests of waste water from pulp and paper industry. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
In this paper, we review the life and work of Mieczyslaw Konopacki and his wife Bronislawa Konopacka. These Polish scientists introduced histochemical methods to embryological studies at the beginning of the XXth century; they were pioneers in this regard in Poland and among the first in the world to implement such methods in this way.  相似文献   

20.
Cellulase was produced by Acremonium cellulolyticus using untreated waste paper sludge (PS) as the carbon source. The clay present in PS did not show any inhibitory effect on cellulase production but did alter the pH during fermentation. On the flask scale, the maleate buffer concentration and pH were key factors that affected the efficiency of cellulase production from PS cellulose. Optimum cellulase production in a 3-L fermentor of working volume 1.5 L was achieved by controlling the pH value at 6.0 using 2 M NaOH and 2 M maleic acid, and the productivity reached 8.18 FPU/mL. When 40.89 g/L PS cellulose, 2.2 g/L (NH(4) )(2) SO(4) , and 4.4 g/L urea were added to a 48-h culture, the cellulase activity was 9.31 FPU/mL at the flask scale and 10.96 FPU/mL in the 3-L fermentor. These values are ~80% of those obtained when pure cellulose is used as the carbon source. The method developed here presents a new route for the utilization of PS.  相似文献   

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