Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction tempera...Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree.展开更多
In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated i...In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics.展开更多
An incubation experiment was conducted to evaluate the potential for water contamination with sludge-derived organic substances and copper following land application of alkaline-stabilised sewage sludge. Twocontrastin...An incubation experiment was conducted to evaluate the potential for water contamination with sludge-derived organic substances and copper following land application of alkaline-stabilised sewage sludge. Twocontrasting sludge-amended soils were studied. Both soils were previously treated with urban and ruralalkaline biosolids separately at sludge application rates of 0, 30 and 120 t ha-1 fresh product. The air-driedsoil/sludge mixtures were wetted with distilled water, maintained at 40 % of water-holding capacity andequilibrated for three weeks at 4 ℃ before extraction. Subsamples were extracted with either distilled wateror 0.5 mol L-1 K2SO4 solution. The concentrations of organic C in the aqueous and chemical extractswere determined directly with a total organic carbon (TOC) analyser. The concentrations of Cu in the twoextracts were also determined by atomic absorption spectrophotometry The relationship between the twoextractable organic C fractions was examined, together with展开更多
Organic matter was experimentally extracted by supercritical fiuids (CO2 +1% isopropanol) from petroleum source rocks of different thermo-maturities at different buried depths in the same stratigraphic unit in the D...Organic matter was experimentally extracted by supercritical fiuids (CO2 +1% isopropanol) from petroleum source rocks of different thermo-maturities at different buried depths in the same stratigraphic unit in the Dongying Basin. The results show that supercritical fluid extraction (SFE) is more effective than Soxhlet extraction (SE), with higher amounts and greater varieties of hydrocarbons and soluble organic matter becoming extractive. The supercritical CO2 extraction is therefore considered more valuable in evaluation of petroleum source rocks and oil resources, particularly those of immature types.展开更多
Soil dissolved organic matter(DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of diffe...Soil dissolved organic matter(DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of different DOM components are poorly understood.We extracted DOM from three soils using different extraction times, solid to liquid ratios(SLR), and extraction solution(KCl)concentrations, and evaluated the extractions using three-dimensional excitation-emission matrix(EEM) fluorescence spectroscopy.The sum of the contents of the main DOM components(protein-, fulvic-, and humic-like compounds) increased by 0.6–3.5, 2.5–3.9,and 0.11–0.37 times(P < 0.05) when SLR decreased from 1:2 to 1:10, the extraction solution concentration increased from 0.01 to 1.5 mol L^(-1), and extraction time increased from 10 to 300 min, respectively. The three-dimensional EEM fluorescence spectroscopy is a useful tool to characterize the components of DOM and evaluate DOM extraction in soils.展开更多
The extraction of the organic matter (OM) from oil shale (OS) can be achieved by several processing techniques. Normally, these techniques can remove high proportion of the organic material contained in oil shale. In ...The extraction of the organic matter (OM) from oil shale (OS) can be achieved by several processing techniques. Normally, these techniques can remove high proportion of the organic material contained in oil shale. In this work, organic solvents extraction experiments were implemented to investigate the effect of various parameters on Jordanian El-Lajjun oil shale extractability. Results indicate that the approximate organic matter content in studied El-Lajjun oil shale is 17.48%, and 75% of OS sample particles diameters are less than 270 μm. The grain size has minor effect on shale oil extraction via organic solvents. Among eleven solvents used, the highest yield is obtained via the tetrahedrofuran (THF), whereas, with the use of solvent mixtures, the highest bitumen yield is obtained through the mixture of THF and toluene. The solvation variability is related to mode of extraction and various physicochemical factors such as extraction temperature, pressure, solvent type and mixing time, which result in different OM yield. The results indicate that the solvent extraction could be potential for shale oil extraction from Jordanian El-Lajjun OS under certain conditions of temperature, pressure and solvent type used.展开更多
Organochlorine pesticides and polychlorinated biphenyls are toxic, carcinogenic, and have a high potential for bioaccumulation. Due to their stability, they are still considered an environmental problem even though th...Organochlorine pesticides and polychlorinated biphenyls are toxic, carcinogenic, and have a high potential for bioaccumulation. Due to their stability, they are still considered an environmental problem even though the use of most of them has been phased out several decades ago. Soil is a matrix which can retain these contaminants to a great extent. This ability is often associated with the total organic carbon content (TOC). In order to judge the pollution status of soil and to make monitoring data more easily comparable a simple, yet robust extraction method is needed. Agitation solid-liquid-extraction is well suited for this purpose. However, the influence of TOC on the analyte recovery has to be known. For the presented study, 12 organochlorine pesticides and 7 polychlorinated biphenyls were spiked into four model soils with organic carbon contents between 1.6% - 13.3%. The matrices were extracted using solid-liquid extraction between 45 minutes and 16 hours. For comparison, all soils were also extracted using pressurised liquid extraction and Soxhlet extraction. After clean-up the extracts were measured using a gas chromatography-mass spectrometry (GC-MS) system. Statistical analysis of the results implied that the TOC content of the soils did not have significant influence on the extraction efficiency. A longer solid-liquid extraction time did not necessarily increase analyte recovery: Extraction for one hour resulted in 88% recovery while 16 hour extraction led to 89%. Thus, the efficiency of all the methods was comparable for all model soils. Additional investigations regarding GC liner performance highlighted the need for isotopically labelled standards during the analysis of thermolabile pesticides.展开更多
This study aims to determine the effect of adding feed supplements of fermented shrimp waste extract in the ration on the digestibility of local chicken rations in the growth phase.The research was carried out in Jati...This study aims to determine the effect of adding feed supplements of fermented shrimp waste extract in the ration on the digestibility of local chicken rations in the growth phase.The research was carried out in Jatinangor District as well as the Laboratory of Ruminant Animal Nutrition and Animal Feed Chemistry,Faculty of Animal Husbandry,Padjadjaran University,Sumedang.The method used in this study was experimental with a Complete Randomized Design(RAL).The data were analyzed by fingerprint test(ANOVA)with further tests using the Dunnet test.The object of this study consisted of 20 Sentul chickens raised from the age of 1 day to 12 weeks,divided into 5 treatments and 4 tests.The treatment consists of P0=Basal ration without the addition of feed supplement fermented shrimp waste extract,P1=Basal ration+0.5%feed supplement fermented shrimp waste extract,P2=Basal ration+1.0%feed supplement fermented shrimp waste extract,P3=Basal ration+1.5%feed supplement fermented shrimp waste extract,and P4=Basal ration+2.0%feed supplement fermented shrimp waste extract.The changes observed are the digestibility of dry matter,the digestibility of organic matter,and the digestibility of proteins.The results showed that the addition of feed supplements for fermented shrimp waste extract had a significantly different influence on the digestibility of dry matter,the digestibility of organic matter,and the digestibility of protein.This study concludes that the addition of a feed supplement of 2%fermented shrimp waste extract in the ration can produce a high ration digestibility value for Sentul chicken in the growth phase.展开更多
Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous...Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous Qingshankou Formation(QF,86–92 Ma)in Songliao basins,by evaluating the organic and inorganic nitrogen isotopic compositions rather than only organic or bulk nitrogen isotopic compositions.The results indicate that the nitrogen isotope values of bulk rock(δ^(15)N_(bulk))in the non-metamorphic stage are significantly different from that of kerogen,which challenge the conceptual framework of sedimentary nitrogen isotope interpretation.Theδ^(15)N_(bulk)from the YF and QF were lower than their respective the nitrogen isotope values of kerogen(δ^(15)N_(ker)),with offsets up to5.1‰,which have the inverse relationship for the metamorphosed rock.Thermal evolution did not significantly modify the d15N of bulk rock and kerogen.The d15N of sediments from the YF(δ^(15)N_(bulk),1.6‰–5.6‰)were lower than that of rock from the QF(δ^(15)N_(bulk),10.2‰–15.3‰).The nitrogen isotope values of silicate incorporated nitrogen(δ^(15)N_(sil))were slightly lower than those of the d15Nker in the YF and obviously lower for the QF.The fact that different nitrogen cycles occur in the YF and QF due to the different depositional redox conditions leads to different isotopic results.The YF water environment dominated by oxic conditions is not conducive to the occurrence of denitrification and anammox,and no abundant N2 loss leads to the relatively lightδ^(15)N_(bulk).In the stratified water for the QF,redox transition zone promotes denitrification and anammox,resulting in the heavyδ^(15)N_(bulk)of rock and promotes the DNRA,resulting in heavyδ^(15)N_(ker)and lowδ^(15)N_(sil).展开更多
Fouling of cellulose triacetate(CTA) forward osmosis(FO) membranes by natural organic matter(NOM) was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as...Fouling of cellulose triacetate(CTA) forward osmosis(FO) membranes by natural organic matter(NOM) was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as the feed solution(FS), and a sodium chloride solution(3 tool/L) was used for the draw solution(DS). The process was conducted at various temperatures and cross-flow velocities. The flux decline was investigated with 3 h forward osmosis operation. The substances absorbed on the membranes were cleaned by ultrasonic oscillation of the fouled membranes and were characterized by methodologies including fluorescence excitation-emission matrices (EEMs) and liquid chromatography with an organic carbon detector(LC-OCD), and the variations of membrane properties were also investigated by Fourier transform infrared spectrometer(FTIR) and a contact angle meter. It was noted that the rejection efficiency of NOM is remarkable and that ultrasonic oscillation is an effective method to extract the NOM fouled on the CTA membranes after FO process. A higher cross-flow velocity and lower temperature benefit the anti-fouling capacity of the membrane significantly. Although humic substances accounted for the majority of the NOM, aromatic proteins and amino acids were the main fouling components on the membranes, with symbolic FTIR peaks at 2355, 1408 and 873 cm^-1. The present surface foulant made the membranes becoming more hydrophilic, as demonstrated by a significant decrease in contact angle(ranging from 20% to 46%) under all the operation conditions.展开更多
The amount and biodegradability of dissolved organic carbon (DOC) in forest floors can contribute to carbon sequestration in soils and the release of CO 2-C from soil to the atmosphere.There is only limited knowledge ...The amount and biodegradability of dissolved organic carbon (DOC) in forest floors can contribute to carbon sequestration in soils and the release of CO 2-C from soil to the atmosphere.There is only limited knowledge about the biodegradation of DOC in soil extracts and leachates due to the limitations inherent in degradation experiments.Differences in the biodegradation of DOC were studied in forest soil extracts using cold and hot water and 4 mmol/L CaCl 2 solution and in soil leachates sampled under different conditions over a wide range of DOC concentrations.From these results,we developed a simple and rapid method for determining the biodegradable organic C in forest floors.The hot water extracts and CaCl 2 extracts after CH 3 Cl fumigation contained higher concentrations of biodegradable organic C than the cold water extracts and CaCl 2 extracts before fumigation,with rapid DOC degradation occurring 24-48 h after incubation with an inoculum,followed by slow DOC degradation till 120-168 h into the incubation.During a 7-d incubation with an inoculum,the variation in DOC degradation in the different soil extracts was consistent with the change in special UV absorbance at 254 nm.Relatively higher levels of biodegradable organic C were detected in soil leachates from the forest canopy than in forest gaps between April and October 2008 (P <0.05).Relatively lower concentrations of DOC and biodegradable organic C were observed in soil leachates from N-fertilized plots during the growing season compared with the control,with the exception of the plot treated with KNO 3 at a rate of 45 kg N ha 1 a 1.Around 77.4% to 96.3% of the variability in the biodegradable organic C concentrations in the forest floors could be accounted for by the initial DOC concentration and UV absorbance at 254 nm.Compared with the conventional inoculum incubation method,the method of analyzing UV absorbance at 254 nm is less time consuming and requires a much smaller sample volume.The results suggest that the regression models obtained using the initial DOC concentration and UV absorbance can provide a rapid,simple and reliable method for determining the biodegradable organic C content,especially in field studies involving relatively large numbers of samples.展开更多
Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle.Given the central role of Al and Fe in stabilizing organic ma...Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle.Given the central role of Al and Fe in stabilizing organic matter in volcanic ash soils,we assessed various extraction methods of Al,Fe,and C fractions from montane volcanic ash soils in northern Ecuador,aiming at elucidating the role of Al and Fe in stabilizing soil organic matter(SOM).We found extractions with cold sodium hydroxide,ammonium oxalate/oxalic acid,sodium pyrophosphate,and sodium tetraborate to be particularly useful.Combination of these methods yielded information about the role of the mineral phase in stabilizing organic matter and the differences in type and degree of complexation of organic matter with Al and Fe in the various horizons and soil profiles.Sodium tetraborate extraction proved the only soft extraction method that yielded simultaneous information about the Al,Fe,and C fractions extracted.It also appeared to differentiate between SOM fractions of different stability.The fractions of copper chloride-and potassium chloride-extractable Al were useful in assessing the total reactive and toxic Al fractions,respectively.The classical subdivision of organic matter into humic acids,fulvic acids,and humin added little useful information.The use of fulvic acids as a proxy for mobile organic matter as done in several model-based approaches seems invalid in the soils studied.展开更多
基金supported by the National Natural Science Foundation of China (51109089 and 31071862)
文摘Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree.
基金supported by the National Nature Science Foundation of China (National Creative Research Groups) (No. 50821002)the State Key Laboratory of Urban Water Resource and Environment,Harbin Instituteof Technology (No. 2008DX05)+2 种基金the Key Projects in the National Science and Technology Pillar Program during the Eleventh Five-year Plan Period (No. 2006BAC19B04)the Heilongjiang Province Science Foundation for Youths(No. QC2009C113/E0804)the Shanghai Tongji GaoTingyao Environmental Science & Technology Development Foundation
文摘In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics.
基金National Natural Science Foundation of China(No.49831070 and 40125005)theNational Key Basic Research Support Foundation (NKBRSF) of China (No. G1999011807) the Jiangsu Provincial Foundation for Young Scientists (No. BQ98050).
文摘An incubation experiment was conducted to evaluate the potential for water contamination with sludge-derived organic substances and copper following land application of alkaline-stabilised sewage sludge. Twocontrasting sludge-amended soils were studied. Both soils were previously treated with urban and ruralalkaline biosolids separately at sludge application rates of 0, 30 and 120 t ha-1 fresh product. The air-driedsoil/sludge mixtures were wetted with distilled water, maintained at 40 % of water-holding capacity andequilibrated for three weeks at 4 ℃ before extraction. Subsamples were extracted with either distilled wateror 0.5 mol L-1 K2SO4 solution. The concentrations of organic C in the aqueous and chemical extractswere determined directly with a total organic carbon (TOC) analyser. The concentrations of Cu in the twoextracts were also determined by atomic absorption spectrophotometry The relationship between the twoextractable organic C fractions was examined, together with
文摘Organic matter was experimentally extracted by supercritical fiuids (CO2 +1% isopropanol) from petroleum source rocks of different thermo-maturities at different buried depths in the same stratigraphic unit in the Dongying Basin. The results show that supercritical fluid extraction (SFE) is more effective than Soxhlet extraction (SE), with higher amounts and greater varieties of hydrocarbons and soluble organic matter becoming extractive. The supercritical CO2 extraction is therefore considered more valuable in evaluation of petroleum source rocks and oil resources, particularly those of immature types.
基金the financial support of the Special Environmental Research Fund for Public Welfare of the State Environmental Protection Administration of China (No.201309035)the Natural Science Foundation of China (No.51408587)
文摘Soil dissolved organic matter(DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of different DOM components are poorly understood.We extracted DOM from three soils using different extraction times, solid to liquid ratios(SLR), and extraction solution(KCl)concentrations, and evaluated the extractions using three-dimensional excitation-emission matrix(EEM) fluorescence spectroscopy.The sum of the contents of the main DOM components(protein-, fulvic-, and humic-like compounds) increased by 0.6–3.5, 2.5–3.9,and 0.11–0.37 times(P < 0.05) when SLR decreased from 1:2 to 1:10, the extraction solution concentration increased from 0.01 to 1.5 mol L^(-1), and extraction time increased from 10 to 300 min, respectively. The three-dimensional EEM fluorescence spectroscopy is a useful tool to characterize the components of DOM and evaluate DOM extraction in soils.
文摘The extraction of the organic matter (OM) from oil shale (OS) can be achieved by several processing techniques. Normally, these techniques can remove high proportion of the organic material contained in oil shale. In this work, organic solvents extraction experiments were implemented to investigate the effect of various parameters on Jordanian El-Lajjun oil shale extractability. Results indicate that the approximate organic matter content in studied El-Lajjun oil shale is 17.48%, and 75% of OS sample particles diameters are less than 270 μm. The grain size has minor effect on shale oil extraction via organic solvents. Among eleven solvents used, the highest yield is obtained via the tetrahedrofuran (THF), whereas, with the use of solvent mixtures, the highest bitumen yield is obtained through the mixture of THF and toluene. The solvation variability is related to mode of extraction and various physicochemical factors such as extraction temperature, pressure, solvent type and mixing time, which result in different OM yield. The results indicate that the solvent extraction could be potential for shale oil extraction from Jordanian El-Lajjun OS under certain conditions of temperature, pressure and solvent type used.
文摘Organochlorine pesticides and polychlorinated biphenyls are toxic, carcinogenic, and have a high potential for bioaccumulation. Due to their stability, they are still considered an environmental problem even though the use of most of them has been phased out several decades ago. Soil is a matrix which can retain these contaminants to a great extent. This ability is often associated with the total organic carbon content (TOC). In order to judge the pollution status of soil and to make monitoring data more easily comparable a simple, yet robust extraction method is needed. Agitation solid-liquid-extraction is well suited for this purpose. However, the influence of TOC on the analyte recovery has to be known. For the presented study, 12 organochlorine pesticides and 7 polychlorinated biphenyls were spiked into four model soils with organic carbon contents between 1.6% - 13.3%. The matrices were extracted using solid-liquid extraction between 45 minutes and 16 hours. For comparison, all soils were also extracted using pressurised liquid extraction and Soxhlet extraction. After clean-up the extracts were measured using a gas chromatography-mass spectrometry (GC-MS) system. Statistical analysis of the results implied that the TOC content of the soils did not have significant influence on the extraction efficiency. A longer solid-liquid extraction time did not necessarily increase analyte recovery: Extraction for one hour resulted in 88% recovery while 16 hour extraction led to 89%. Thus, the efficiency of all the methods was comparable for all model soils. Additional investigations regarding GC liner performance highlighted the need for isotopically labelled standards during the analysis of thermolabile pesticides.
文摘This study aims to determine the effect of adding feed supplements of fermented shrimp waste extract in the ration on the digestibility of local chicken rations in the growth phase.The research was carried out in Jatinangor District as well as the Laboratory of Ruminant Animal Nutrition and Animal Feed Chemistry,Faculty of Animal Husbandry,Padjadjaran University,Sumedang.The method used in this study was experimental with a Complete Randomized Design(RAL).The data were analyzed by fingerprint test(ANOVA)with further tests using the Dunnet test.The object of this study consisted of 20 Sentul chickens raised from the age of 1 day to 12 weeks,divided into 5 treatments and 4 tests.The treatment consists of P0=Basal ration without the addition of feed supplement fermented shrimp waste extract,P1=Basal ration+0.5%feed supplement fermented shrimp waste extract,P2=Basal ration+1.0%feed supplement fermented shrimp waste extract,P3=Basal ration+1.5%feed supplement fermented shrimp waste extract,and P4=Basal ration+2.0%feed supplement fermented shrimp waste extract.The changes observed are the digestibility of dry matter,the digestibility of organic matter,and the digestibility of proteins.The results showed that the addition of feed supplements for fermented shrimp waste extract had a significantly different influence on the digestibility of dry matter,the digestibility of organic matter,and the digestibility of protein.This study concludes that the addition of a feed supplement of 2%fermented shrimp waste extract in the ration can produce a high ration digestibility value for Sentul chicken in the growth phase.
基金supported by the National Natural Science Foundation of China(General Program,No.41972127)the National Key Research and Development Program of China(No.2021YFA0719000)。
文摘Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous Qingshankou Formation(QF,86–92 Ma)in Songliao basins,by evaluating the organic and inorganic nitrogen isotopic compositions rather than only organic or bulk nitrogen isotopic compositions.The results indicate that the nitrogen isotope values of bulk rock(δ^(15)N_(bulk))in the non-metamorphic stage are significantly different from that of kerogen,which challenge the conceptual framework of sedimentary nitrogen isotope interpretation.Theδ^(15)N_(bulk)from the YF and QF were lower than their respective the nitrogen isotope values of kerogen(δ^(15)N_(ker)),with offsets up to5.1‰,which have the inverse relationship for the metamorphosed rock.Thermal evolution did not significantly modify the d15N of bulk rock and kerogen.The d15N of sediments from the YF(δ^(15)N_(bulk),1.6‰–5.6‰)were lower than that of rock from the QF(δ^(15)N_(bulk),10.2‰–15.3‰).The nitrogen isotope values of silicate incorporated nitrogen(δ^(15)N_(sil))were slightly lower than those of the d15Nker in the YF and obviously lower for the QF.The fact that different nitrogen cycles occur in the YF and QF due to the different depositional redox conditions leads to different isotopic results.The YF water environment dominated by oxic conditions is not conducive to the occurrence of denitrification and anammox,and no abundant N2 loss leads to the relatively lightδ^(15)N_(bulk).In the stratified water for the QF,redox transition zone promotes denitrification and anammox,resulting in the heavyδ^(15)N_(bulk)of rock and promotes the DNRA,resulting in heavyδ^(15)N_(ker)and lowδ^(15)N_(sil).
基金Supported by the National Natural Science Foundation of China(Nos.51178322, 51378367) and the National Science and Technology Maj or Project, China(Nos.2012ZX07408-001, 2012ZX07404-004).
文摘Fouling of cellulose triacetate(CTA) forward osmosis(FO) membranes by natural organic matter(NOM) was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as the feed solution(FS), and a sodium chloride solution(3 tool/L) was used for the draw solution(DS). The process was conducted at various temperatures and cross-flow velocities. The flux decline was investigated with 3 h forward osmosis operation. The substances absorbed on the membranes were cleaned by ultrasonic oscillation of the fouled membranes and were characterized by methodologies including fluorescence excitation-emission matrices (EEMs) and liquid chromatography with an organic carbon detector(LC-OCD), and the variations of membrane properties were also investigated by Fourier transform infrared spectrometer(FTIR) and a contact angle meter. It was noted that the rejection efficiency of NOM is remarkable and that ultrasonic oscillation is an effective method to extract the NOM fouled on the CTA membranes after FO process. A higher cross-flow velocity and lower temperature benefit the anti-fouling capacity of the membrane significantly. Although humic substances accounted for the majority of the NOM, aromatic proteins and amino acids were the main fouling components on the membranes, with symbolic FTIR peaks at 2355, 1408 and 873 cm^-1. The present surface foulant made the membranes becoming more hydrophilic, as demonstrated by a significant decrease in contact angle(ranging from 20% to 46%) under all the operation conditions.
基金supported by the National Basic Research Program of China (2010CB950602)the National Natural Science Foundation of China (40875085,41021004 and 41175133)
文摘The amount and biodegradability of dissolved organic carbon (DOC) in forest floors can contribute to carbon sequestration in soils and the release of CO 2-C from soil to the atmosphere.There is only limited knowledge about the biodegradation of DOC in soil extracts and leachates due to the limitations inherent in degradation experiments.Differences in the biodegradation of DOC were studied in forest soil extracts using cold and hot water and 4 mmol/L CaCl 2 solution and in soil leachates sampled under different conditions over a wide range of DOC concentrations.From these results,we developed a simple and rapid method for determining the biodegradable organic C in forest floors.The hot water extracts and CaCl 2 extracts after CH 3 Cl fumigation contained higher concentrations of biodegradable organic C than the cold water extracts and CaCl 2 extracts before fumigation,with rapid DOC degradation occurring 24-48 h after incubation with an inoculum,followed by slow DOC degradation till 120-168 h into the incubation.During a 7-d incubation with an inoculum,the variation in DOC degradation in the different soil extracts was consistent with the change in special UV absorbance at 254 nm.Relatively higher levels of biodegradable organic C were detected in soil leachates from the forest canopy than in forest gaps between April and October 2008 (P <0.05).Relatively lower concentrations of DOC and biodegradable organic C were observed in soil leachates from N-fertilized plots during the growing season compared with the control,with the exception of the plot treated with KNO 3 at a rate of 45 kg N ha 1 a 1.Around 77.4% to 96.3% of the variability in the biodegradable organic C concentrations in the forest floors could be accounted for by the initial DOC concentration and UV absorbance at 254 nm.Compared with the conventional inoculum incubation method,the method of analyzing UV absorbance at 254 nm is less time consuming and requires a much smaller sample volume.The results suggest that the regression models obtained using the initial DOC concentration and UV absorbance can provide a rapid,simple and reliable method for determining the biodegradable organic C content,especially in field studies involving relatively large numbers of samples.
基金Supported by the Netherlands Foundation for the Advancement of Tropical Research (NWO-WOTRO) (Nos.WAN 75-405and WAN 75-406)
文摘Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle.Given the central role of Al and Fe in stabilizing organic matter in volcanic ash soils,we assessed various extraction methods of Al,Fe,and C fractions from montane volcanic ash soils in northern Ecuador,aiming at elucidating the role of Al and Fe in stabilizing soil organic matter(SOM).We found extractions with cold sodium hydroxide,ammonium oxalate/oxalic acid,sodium pyrophosphate,and sodium tetraborate to be particularly useful.Combination of these methods yielded information about the role of the mineral phase in stabilizing organic matter and the differences in type and degree of complexation of organic matter with Al and Fe in the various horizons and soil profiles.Sodium tetraborate extraction proved the only soft extraction method that yielded simultaneous information about the Al,Fe,and C fractions extracted.It also appeared to differentiate between SOM fractions of different stability.The fractions of copper chloride-and potassium chloride-extractable Al were useful in assessing the total reactive and toxic Al fractions,respectively.The classical subdivision of organic matter into humic acids,fulvic acids,and humin added little useful information.The use of fulvic acids as a proxy for mobile organic matter as done in several model-based approaches seems invalid in the soils studied.