Effects of organic chromium supplementation to finishing lambs diet on growth performance, carcass characteristics and meat quality

The objective of this study was to evaluate supplemental organic chromium（Cr） to finishing lambs on growth performance, carcass characteristics, and meat quality. Eighteen Suffolk lambs（age（4.5±0.2） mon;（25.8±3.6） kg body weight（BW）） were randomly assigned to three levels of supplemental organic Cr（0.0, 0.2 and 0.4 mg kg^–1 dry matter（DM）） in a complete random design. Growth performance was evaluated for 70 d, and then lambs were slaughtered to study carcass characteristics and chemical composition of meat. Orthogonal contrasts were performed（contrast one-average level 0.2 ppm Cr vs. average level 0.4 ppm Cr; contrast two-level 0 vs. average levels（0.2＋0.4） ppm Cr）. Orthogonal polynomials were used to estimate the linear and quadratic effects of Cr concentrations. Growth and carcass performance were not affected by supplemental organic Cr. Muscle conformation and leg perimeter linearly increased（P〈0.05） as organic Cr level increased in the diet. Kidney fat decreased linearly（P〈0.05） as supplemental Cr increased. In Longissimus dorsi（LD）, the ash content decreased linearly, and shear force（kg cm^–2） increased（P〈0.05） as organic Cr level increased in the diet. It is concluded that organic Cr did not affect growth performance, but it improved positively the muscle conformation, reduced kidney fat, whereas in LD there was an increment in shear force in finishing carcass lambs.

Effects of feeding yeast(Saccharomyces cerevisiae), organic selenium and chromium mixed on growth performance and carcass traits of hair lambs

Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs（Pelibuey×Katahdin; BW=（30.55±1.67） kg; n=8） were used in a 56-d feeding experiment to study the effects of different levels of live yeast（Saccharomyces cerevisiae; yeast）, selenium（Se） and chromium（Cr） mixed（Se-Cr）, and a mixture of yeast-Se-Cr on growth performance and carcass traits. Animals were stratified by body weight（BW） and randomly assigned to one of four treatments： 1） control group（0.0 g kg–1 yeast）; 2） yeast（1.50 g kg–1 dry matter intake（DMI） d–1）; 3） Se-Cr premix（1.5 mg kg–1 DMI d–1 for each mineral）; and 4） yeast-Se-Cr mixture. There were no treatment effects on final BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher（P〈0.05） DMI than animals supplemented with only yeast. Average daily gain（ADG）, gain：feed ratio, chop area, dorsal fat and carcass yield were similar（P〉0.05） among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and yeast-Se-Cr increased DMI, and approximately 250 g ADG animal–1 d–1 was produced with no negative effects on growth and health of the animals.

Chromium-Containing Organic Fertilizers from Tanned Hides and Skins: A Review on Chemical, Environmental, Agronomical and Legislative Aspects

A category of chromium (Cr)-containing fertilizers is represented by the fertilizers deriving from byproducts of tanning process. Their use is widespread because of their good agronomic response due to the high content of slow release or- ganic nitrogen (N) and carbon (C). They do not represent an environmental hazard because only the non-toxic form of Cr(III) is present. Productive processes may involve chemical, enzymatic or thermal hydrolysis. The final product is characterized by different contents of peptides and free amino acids depending on the type of hydrolysis. Legislation concerning Cr-containing fertilizers is controversial because often do not consider any scientific evidences;nevertheless, the European Union, the United States and countries as Italy, do not set the restriction to Cr(III) and generally only the presence of the toxic form, Cr(VI), is limited. Depending on its two main oxidation forms, Cr issue has been studied for many years. Several authors confirmed that Cr(VI) is carcinogenic, while Cr(III) is an essential trace element in human and animal diet. In soil Cr(III) has low mobility, whereas Cr(VI) is highly water soluble. However Cr(VI) in soil is quickly reduced to Cr(III);on the contrary oxidation of Cr(III) to Cr(VI) is rarely possible because particular conditions must occur. Only a very small fraction of Cr in soil is available to plant uptake and its translocation in edible parts is limited because it is immobilized in roots as Cr(III). Therefore risks of environmental pollution using these fertilizers are negligible;on the contrary they have positive environmental and agronomical effects. The aim of this review is to deal with the category of the organic fertilizers containing Cr derived from tannery processes focusing on its chemical, productive, legislative, environmental and agronomical aspects. Special attention is given to the ambiguous issue of Cr briefly summarizing the most important studies of the last forty years.

Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater

Adsorption kinetics of the interaction between Pt, Pd and Rh(defined here as platinum group elements, PGEs)ions and macromolecular organic compounds(MOCs,>10 kDa), including humic acid, carrageenan and bovine serum albumin, and different cutoff fractions of natural organic matter(>1 kDa and >3 kDa) obtained from seawater using centrifugal ultrafiltration devices were investigated. For a given element, all the adsorption kinetics did not reach equilibrium except the interaction between Pt and >1 kDa cutoff, and between Pd and humic acid.For all the tested MOCs, the adsorption kinetics could be divided into two stages, a rapid adsorption process in the first 8 h and the desorption stage after the first 8 h until the equilibrium. The change trend of partition coefficient(log10Kd) values with experiment time was consistent with that of the kinetic curves. However, in the interaction between PGE ions and natural dissolved organic matter(NDOM), an obvious difference in the change trends of log10Kd and kinetic curves was observed. It indicated that the partition behavior of PGE ions interacting with NDOM in seawater was a combined effect of different organic constituents. The adsorption and log10Kd of PGEs in the >1 kDa NDOM fraction were higher and more stable than those in the >3 kDa NDOM fraction. The results also indicated that the 1–3 kDa NDOM may dominate the interaction between PGEs ions and NDOM. Moreover, no kinetic model could perfectly simulate the adsorption process. It indicated that the colloidal struction and morphology of MOCs or NDOM in seawater might be inhomogeneous. Hence, the interaction between PGE ions and organic matter in seawater was a complicated process and needs further research.

TRANSFER OF ORGANIC POLLUTANTS DURING SEW AGE-SEAWATER MIXING

The transfer processes of organic pollutants during sewage - seawater mixing were simulated in three different mixing systems. The release rate of organic matter from sewage particles to seawater was found to be about 0.02-0.04d-1 . The release processes can be simulated by an exchange-equilibrium kinetic model. Degradation of COD was observed in all three mixing systems and can be described by a first order kinetic equation. The degradation rate constant k ranged between 0.04 and 0.07 d . These results have provided important parameters for estimation of environmental capacity.

Transformation and immobilization of hexavalent chromium in the co-presence of biochar and organic acids:effects of biochar dose and reaction time

A batch experiment was conducted to examine the effects of biochar dose and reaction duration on the transformation and immobilization of Cr(VI)in the combined biochar and low-molecular-weight organic acid systems.The results showed that increase in the dosage level of biochar caused increase in the solution pH,particularly for the Biochar300 treatments but did not enhance the reduction of Cr(VI)after 1-day reaction.Over 35%of the converted Cr(III)was immobilized by sorption to the biochar due to increased negatively charged sites on the biochar surfaces driven by pH rise.The elevated pH due to biochar dose increase tended to slow down the reduction of Cr(VI)to Cr(III),resulting in more Cr(VI)being adsorbed at a higher biochar dose.For the higher-temperature biochars,the increase in biochar dose did not markedly change the transformation and immobilization of the added Cr.Increase in the reaction duration markedly increased the pH for Biochar300.This resulted in the disappearance of all Cr(VI)in the solution after the 7-day reaction,possibly through sorption of cationic Cr(III)to the biochar surfaces.Increase in reaction time for the higher-temperature biochars resulted in re-oxidation of Cr(III)to Cr(VI)due to the increased exposure of solution Cr(III)to atmospheric oxygen.The research findings obtained from this study have implications for optimizing treatment procedure for wastewater that contains elevated level of toxic Cr(VI).Simulation experiments are required to determine appropriate biochar dose and reaction time to achieve cost-effective treatment goals.

Microwave-assisted Fenton-like decolorization of methyl orange solution using chromium compounds

Azo dyes discharged in the environment are persistent organic pollutants （POPs）, which are very difficult to remove. We developed a microwave-assisted Fenton-like process to degrade methyl orange （MO）, an azo dye, with hydrogen peroxide （H2O2） catalyzed by chromium compounds coexisting with MO in the solution. Comparison between the Cr（Ⅲ）-H2O2 and Cr（Ⅵ）-H2O2 systems shows＂ that Cr（Ⅵ） has a stronger and more stable catalytical activity than Cr（Ⅲ）, and Cr（Ⅲ） is more susceptible to a change in the acidity or alkalinity of the reaction system. With a Cr（Ⅵ） concentration of 10 mmol L^-1 or a Cr（Ⅲ） concentration of 12 mmol L^-1 in the solution under the microwave irradiation of a power larger than 300 W for 3 min, 10 mmol L^-1 H2O2 can degrade more than 95% of 1 000 mg L^-1 methyl orange; when the microwave power is increased to 700 W, the same amount of H2O2 can degrade all methyl orange in the solution with the same amount of Cr（Ⅵ ） catalyst. Ultraviolet-visible spectrography indicates the cleavage of the azo bond in methyl orange after treatment, suggesting the potential o of this Fenton-like process to degrade azo dye POPs. Reusing waste chromium compounds coexisting with dyestuff in wastewater to catalyze the degradation of azo dyes could be a cost-effective technique for azo dyes and chromate manufacturers and/or users to treat their wastewater and prevent POPs from endangering the environment. This is of particula importance to controlling the water quality of the Three Gorges Reservoir.

Effect of Seawater Stress on Physiological and Biochemical Responses of Five Jerusalem Artichoke Ecotypes

Three treatments consisting of 0%,15%,and 30%seawater were investigated to analyse the ecotypic variabilities among five populations of Jerusalem artichoke(Helianthus tuberosus)regarding their responses to seawater stress under a hydroponic culture system.Analyses were done 2,4,and 6 days after treatments.The 15%and 30%seawater treatments reduced the growth rates of roots and shoots of H.tuberosus populations.The activities of superoxide dismutase, peroxidase,and catalase majored in the leaves were stimulated under the seawater stress.The electrolyte leakage and malondialdehyde contents of the leaves were also stimulated owing to seawater stress.The contents of proline and soluble- sugars in the leaves increased significantly with increasing seawater concentrations.The concentrations of Na+,K+,and Cl-in the aerial parts and roots increased with an increase in the seawater concentration throughout the experimental period.There were ecotypic differences among the five populations of H.tuberosus as evidenced by the analyses of the above items in both aerial parts and roots under seawater treatment.The magnitude of the ecotypic variance components indicated that a substantial proportion of the total variation for these physiological and biochemical responses were owing to ecotype,indicating the possibility of improvement through hybridization and selection.

Chemical characterization and composition of dissolved organic matter in Jiaozhou Bay

Biologically utilizable dissolved organic compounds,including dissolved organic carbon (DOC),dissolved carbohydrates (DCHO) and dissolved free amino acids (DFAA) were analyzed in filtered surface seawater samples collected at 19 stations in Jiaozhou Bay,China,on June 3,2007.In these samples,concentrations of DOC,dissolved free carbohydrates (DFCHO),dissolved combined carbohydrates (DCCHO),total dissolved carbohydrates (TDCHO) and total dissolved free amino acids (TDFAA) ranged from 141.7 to 191.1 μmol C/L,1.98 to 18.18 μmol C/L,5.04 to 24.90 μmol C/L,14.52 to 30.36 μmol C/L,and 1.83 to 11.89 μmol C/L,respectively.As a major component of the dissolved carbohydrates,the concentrations of DCCHO were about three times higher than those of DFCHO.Three major constituents of the DFAA were threonine (23.0±5.7 mol%),glutamic acid (16.6±3.2 mol%) and arginine (9.1±3.3 mol%).Based on the composition of DFAA,a molar C:N ratio of 3.60±0.75 in DFAA was derived,indicating longer carbon chains in the amino acids.DCCHO (8.1%) was the most abundant fraction of DOM in most samples,followed by DFCHO (4.8%) and TDFAA (2.7%).These DOM concentrations displayed a decreasing trend from the coast to the central region.Significant correlations were found between the DCCHO and DFCHO concentrations (r=-0.724,n=19,P<0.001) and the DCCHO and TDCHO concentrations (r=0.506,n=19,P=0.027).

In-situ polarization of covalent organic frameworks in seawater enables enhanced photocatalytic hydrogen evolution under visiblelight irradiation

Photocatalytic hydrogen(H_(2))production from seawater over a photocatalyst is of great significance for the utilization of the earth’s abundant seawater resources and the storage of inexhaustible solar energy with low-energy density.However,the designation of efficient photocatalytic systems by using seawater usually suffers from activation decline when replacing pure water with seawater.Herein,we synthesized threeβ-ketoenamine-linked covalent organic frameworks(COFs),demonstrating their promotion in the photocatalytic decomposition of seawater relative to pure water under visible-light irradiation.The target COFs were synthesized via a microwave assisted solvothermal method by using 1,3,5-triformylphloroglucinol(Tp)as the aldehyde monomer to react with diamino units with different numbers of benzene rings.By surveying the building blocks,the constructed COF with a high density ofβ-ketoenamine units exhibited the so far highest photocatalytic H_(2) evolution rate(41.3 mmol·g^(−1)·h^(−1))in seawater,about 1.66 times higher than that in pure water.Theβ-ketoenamine units allowed the in-situ polarization of the COF framework through the adsorption of metal salts when proceeding with the photocatalytic H_(2) production in seawater.This polarization effect significantly increases the dielectric constant of the organic semiconductor to lower exciton dissociation energy and thus enhances the charge separation and transfer to promote the H_(2) photoproduction in seawater.

Determination of Selected Toxic Elements in Apples from Organic Farming

Due to the elevated ecological awareness nowadays the consumption of products of organic agriculture is increasing. Organic farming means excluding the use of synthetic inputs, such as synthetic fertilizers and pesticides or genetically modified organisms, but there are only a few regulations regarding heavy metal concentrations in soils. Thus a not negligible uptake of metals from the soil where the apple trees are grown may occur. Furthermore inorganic copper compounds being traditional fertilizers for apple trees are not considered as synthetic fertilizers, thus they are still used in organic apple farming for soil or foliar application. Thus also apples produced by organic agriculture may contain toxic elements, such as cadmium, chromium, copper, and lead. The concentrations of these elements were determined in whole apples, as well as in the flesh and peel in order to estimate the possible risk for human health. Prior to analysis using ICP-AES samples underwent a microwave assisted digestion. The LODs obtained are below the recommended maximum levels in vegetables/fruits by WHO. In all samples no Cu, Cr, and Pb could be detected. Only Ca was found in the peel of about a third of samples investigated in concentrations between LOD and LOQ （1-3 μg/g）.

Removal of Some Toxic Ions from Seawater and Wastewater by Sorption onto Natural, Synthetic Hydroxyapatite and Alginate-Hydroxyapatite Composite Nanoparticles: A Comparative Study

The main objective of this paper is to study the removal of Cadmium(II), Lead(II), Chromium(VI), and Mercury(II) ions by sorption onto different natural and synthetic nanoparticles. Special attention has been given to the application of fish bone in nanoform as a useful, inexpensive and eco-friendly alternative material. A comparison between natural hydroxyapatite (fish bone), synthetic hydroxyapatite nanoparticles (HAP) and alginate-hydroxyapatite composite (Alg/Hap) to assess their removal efficiencies to remediate the selected heavy metals has been done. Surface characterization by using different techniques has also been performed to understand the influence of surface characteristics of the adsorbent materials in the removal process. Different parameters (pH, contact time, mass dose and metal ion concentration) have been examined to identify the optimum conditions for remediation of different metals from polluted water. The potential applications of the biosorbents for removal and sorption of these metal ions from seawater and wastewater samples were also investigated and evaluated.

Chinese Scientists Working on Diseases of Cultured Organisms in Seawater

Considerable research efforts are being made in China to understand the pathogeny of major marine cultured organisms and their resistance to diseases, which has been listed in the national development program for major basic research projects. The program, also called "973," is in effect a national plan focused on the leading basic

Effects of seawater salinity on nitrite accumulation in short-range nitrification to nitrite as end product

The effect of seawater salinity on nitrite accumulation in short-range nitrification to nitrite as the end product was studied by using a SBR. Experimental results indicated that the growth of nitrobacteria was inhibited and very high levels of nitrite accumulation at different salinities were achieved under the conditions of 25—28℃, pH 7.5? ?.0 , and the influent ammonia nitrogen of 40—70 mg/L when seawater flow used to flush toilet was less than 35%(salinity 12393 mg/L, Cl - 6778 mg/L) of total domestic wastewater flow, which is mainly ascribed to much high chlorine concentration of seawater. Results showed that high seawater salinity is available for short-range nitrification to nitrite as the end product. When the seawater flow used to flush toilet accounting for above 70% of the total domestic wastewater flow, the removal efficiency of ammonia was still above 80% despite the removal of organics declined obviously(less than 60%). It was found that the effect of seawater salinity on the removal of organics was negative rather than positive one as shown for ammonia removal.

Influence of solar eclipse on seawater

Eclipse induced changes in solar radiation is a common interest of scientists all over the world. The disturbance of the heat balance along the supersonic travel of the trajectory of the Moon’s shadow could generate gravity waves during solar eclipse, which results a reduction in the concentration of ozone layer in the stratosphere. We, in this context, conducted some experiments to detect the possible radiations reaching the surface of the earth and the impact of such radiation in seawater during the recent total and annular solar eclipses. This is the first time that the variation in pH value of seawater during solar eclipse is examined, and the experimental data demonstrated that the solar eclipse phenomenon affects the pH value of seawater due to the shorter wavelength radiations received on the surface of the earth. The reduction is around 20% and 40% of the difference between ordinary water and seawater during total and annular eclipses respectively. The multidisciplinary influences of these findings are addressed.

Study of a New Chromium-Free Conversion Coating Formed on ZnAl Alloy

A new chromium-free conversion film was obtained on surface of a ZnAl alloy by chemical conversion process. Influence of the additives in treating solution containing cerium salt on the corrosion protection of the conversion film formed on zinc alloy was investigated. Corrosion tests and electrochemical measurements in sodium chloride solution were performed . The microstructure and composition of the coatings were examined by means of SEM, EDS and XRD. It was found that the corrosion protection capabilities of the conversion film are markedly increased with the cerium nitride plus additives (hydrogen fluoride acid and an organic inhibitor) treating process. The modified conversion film is an organic/inorganic composite coating and is much more corrosion resistant than the conventional chromate conversion coating and the single cerium conversion coating.

Assembly of a core–shell MOF with stability into polyacrylamide hydrogel for boosting extraction of uranium from seawater

Efficient and selective extraction of uranium(U(VI))from seawater is essential for sustainable nuclear power production.This study reports a novel adsorbent zeolitic imidazolate framework(ZIF)-67@SiO_(2)-A/polyacrylamide(PAM)which was synthesized by grafting the core–shell metal–organic frameworks(MOFs)-based nanostructures coated with the 3-aminopropyl triethoxysilane(APTES)functionalized SiO_(2)(SiO_(2)-A)onto PAM hydrogel.The SiO_(2) shell was grown on the surface of MOF,which improved the acid-base resistance of MOF.The introduction of ZIF-67@SiO_(2)-A enhances the specific surface area and adsorption efficiency of the PAM.The ZIF-67@SiO_(2)-A/PAM shows remarkable adsorption capacity,fast adsorption kinetics,and good reusability for uranium.It has excellent adsorption property(6.33 mg·g^(-1),30 d)in natural seawater.The X-ray photoelectron spectroscopy(XPS),Fourier transform infrared(FTIR),energy dispersive spectroscopy(EDS)mappings,and density functional theory reveal that the coordination by N and O in ZIF-67@SiO_(2)-A/PAM with uranium is the main mechanism of uranium adsorption.Thus,ZIF-67@SiO_(2)-A/PAM has great potential to capture uranium from natural seawater.

Thiophene-based covalent organic frameworks for highly efficient iodine capture

Development of adsorbent materials for highly efficient iodine capture is high demand from the perspective of ecological environment and human health. Herein, the two kinds of thiophene-based covalent organic frameworks(COFs) with different morphologies were synthesized by solvothermal reaction using thieno[3,2-b]thiophene-2,5-dicarbaldehyde(TT) as the aldehyde monomer and tri(4-aminophenyl)benzene(PB) or tris(4-aminophenyl)amine(PA) as the amino monomer(denoted as PB-TT COF and PA-TT COF) and the as-prepared two heteroatoms-rich COFs possessed many excellent properties,including high thermal stability and abundant binding sites. Among them, PB-TT COF exhibited ultra-high iodine uptake up to 5.97 g/g in vapor, surpassing most of adsorbents previously reported, which was ascribed to its high specific surface(1305.3 m2/g). Interestingly, PA-TT COF with low specific surface(48.6m2/g) showed good adsorption ability for iodine in cyclohexane solution with uptake value of 750 mg/g,which was 2.38 times higher than that obtained with PB-TT COF due to its unique sheet-like morphology.Besides, the two COFs possessed good reusability, high selectivity and iodine retention ability. Based on experimental results, the adsorption mechanisms of both COFs were studied, revealing that iodine was captured by the physical-chemical adsorption. Furthermore, the both COFs showed excellent adsorption ability in real radioactive seawater treated safely, demonstrating their great potential in real environment.

Cr(Ⅵ) reduction capability of humic acid extracted from the organic component of municipal solid waste

The capacity of humic acid extracted from organic waste （HAw） to reduce Cr（Ⅵ） was tested at pH 2.5,4 and 6 and compared with coal-derived humic acid （HAc）.HAw was more effective than HAc in reducing Cr（Ⅵ）.The kinetics of Cr（Ⅵ） reductions depended strongly on pH.The calculation of the apparent rate coefficients indicated that HAw was more efficient at reducing Cr（Ⅵ） than HAc,but was also more efficient than HAs from soil and peat.The reduction capability of HAs depends on the type of functional groups （i.e.,thiols and phenols） present,rather than the free radicals.HAw was more efficient at reducing Cr（Ⅵ） than HAc because more reactive phenols were present,i.e.,methoxy-and methyl-phenols.

Construction of Ionic Porous Organic Polymers(iPOPs)via Pyrylium Mediated Transformation

Two new ionic porous organic polymers(iPOPs)with different counter anions were successfully fabricated via well-known pyrylium mediated transformation into pyridinium.13C solid-state NMR,XPS,and FTIR were analyzed and confirmed the formation of pyridinium in the network.Containing charged and aromatic networks,both iPOPs exhibit a high affinity towards toxic hexavalent chromium Cr(Ⅵ)ions.What is more,it has been demonstrated that both CO2 adsorption and Cr(Ⅵ)removal properties can be tuned by simply varying counter anions.