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171.
In the current study it was aimed to investigate the toxicity of low doses of imidacloprid (IMI) on the reproductive organ systems of adult male rats. The treatment groups received 0.5 (IMI-0.5), 2 (IMI-2) or 8 mg IMI/kg body weight by oral gavage (IMI-8) for three months. The deterioration in sperm motility in IMI-8 group and epidydimal sperm concentration in IMI-2 and IMI-8 groups and abnormality in sperm morphology in IMI-8 were significant. The levels of testosterone (T) and GSH decreased significantly in group IMI-8 compared to the control group. Upon treatment with IMI, apoptotic index increased significantly only in germ cells of the seminiferous tubules of IMI-8 group when compared to control. Fragmentation was striking in the seminal DNA from the IMI-8 group, but it was much less obvious in the IMI-2 one. IMI exposure resulted in elevation of all fatty acids analyzed, but the increases were significant only in stearic, oleic, linoleic and arachidonic acids. The ratios of 20:4/20:3 and 20:4/18:2 were decreased and 16:1n-9/16:0 ratio was increased. In conclusion, the present animal experiments revealed that the treatment with IMI at NOAEL dose-levels caused deterioration in sperm parameters, decreased T level, increased apoptosis of germ cells, seminal DNA fragmentation, the depletion of antioxidants and change in disturbance of fatty acid composition. All these changes indicate the suppression of testicular function.  相似文献   
172.
Toxaphene is a mixture of more than 200 polychlorinated C10-terpenes. Due to its persistence and long-range transport, it is distributed all over the world. Many of the components are very stable under environmental conditions, while others are easily degraded by UV-light or microorganisms. The main conversion pathway is reductive dechlorination and dehydrochlorination; oxidative degradation possibly occurs only after previous dechlorination. Accumulation especially in the aquatic environment has led in many cases to high residue levels in fish, marine mammals, and sea birds of the northern hemispere. Toxaphene is mutagenic in the Ames test and of high toxicity for fish, but few data are available on the toxicity of single components or their mode of action.  相似文献   
173.
Forests have traditionally been managed to maximize timber production or economic profit, completely neglecting other forest values. Nowadays, however, forests are being managed for multiple uses. The basic requirement of multiple use forestry is to identify and quantify forest values and to determine management objectives. The priorities of management objectives, however, must be decided. In this study, a model predicting the soil loss for multi objective forest management was developed. The model was based on data from remeasurement of permanent sample plots. The data were gathered from 132 sample plots. Approximately 80% of the observations were used for model development and 20% for validation. The model was designed for even aged and uneven aged forests, as well as for forests with mixed and pure species composition. The explicatory variables in the model were mean diameter and number of trees. All parameter estimates were found highly significant (p < 0.001) in predicting soil loss. The model fit and validation tests were fairly good. The soil loss model presented in this paper was considered to have an appropriate level of reliability. It can be used in the overall multi-objective forest management planning, but, it should be limited to the conditions for which the data were gathered.  相似文献   
174.
This article reports the complete mineralization of atrazine. Atrazine has been the most widely used s-triazine herbicide. Atrazine occurs in natural waters and presents a potential danger for public health because atrazine is considered as an endocrine disruptor. The use of chemical, photochemical and photocatalytic advanced oxidation processes (AOPs) to decontaminate waters containing atrazine only allowed its conversion into the cyanuric acid as ultimate end products, since it cannot be completely degraded by hydroxyl radicals (OH) produced by these techniques. The same behavior was previously reported for anodic oxidation and electro-Fenton with Pt anode, although better performances were found using boron-doped diamond (BDD) anode but without explaining the role of generated OH. Here, the oxidative action of these radicals in such electrochemical AOPs has been clarified by studying the mineralization process and decay kinetics of atrazine and cyanuric acid in separated solutions by anodic oxidation with BDD and electro-Fenton with Pt or BDD anode using an undivided cell with a carbon-felt cathode under galvanostatic conditions. Results showed that electro-Fenton with BDD anode was the more powerful treatment to degrade both compounds. Almost total mineralization, 97% total organic carbon (COT) removal, of atrazine was only feasible by this method with a faster removal of its oxidation intermediates by OH formed at the BDD surface than that formed in the bulk from Fenton reaction, although the latter process caused a more rapid decay of the herbicide. Cyanuric acid was much slowly mineralized mainly with OH produced at the BDD surface, and it was not degraded by electro-Fenton with Pt anode. These results highlight that electrochemical advanced oxidation processes (EAOPs) using a BDD anode are more powerful than the classical electro-Fenton process with Pt or PbO2 anodes.  相似文献   
175.
In this study, recycling of spent coffee grounds (SCG) as a potential feedstock for alternative fuel production and compounds of added value in Turkey was assessed. The average oil content was found (≈ 13% w/w). All samples (before and after extraction) were tested for scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), calorific value, surface analysis and porosity, Fourier transform infrared (FT-IR), and elemental analysis to assess their potential towards fuel properties. Elemental analysis indicated that carbon represents the highest percentages (49.59% and 46.42%, respectively), followed by nitrogen (16.7% and 15.5%), hydrogen (6.74% and 6.04%), and sulfur (0.851% and 0.561%). These results indicate that SCG can be utilized as compost, as it is rich in nitrogen. Properties of the extracted oil were examined, followed by biodiesel production. The quality of biodiesel was compared with American Society for Testing and Materials (ASTM) D6751 standards, and all the properties complied with standard specifications. The fatty acid compositions were analyzed by gas chromatography. It was observed that coffee waste methyl ester (CWME) is mainly composed of palmitic (35.8%) and arachidic (44.6%) acids, which are saturated fatty acids. The low degree of unsaturation provides an excellent oxidation stability (10.4 hr). CWME has also excellent cetane number, higher heating value, and iodine value with poor cold flow properties. The studies also investigated blending of biodiesel with Euro diesel and butanol. Following this, a remarkable improvement in cloud and pour points of biodiesel was obtained. Spent coffee grounds after oil extraction is an ideal material for garden fertilizer, feedstock for ethanol, biogas production, and as fuel pellets. The outcome of such research work produces valuable insights on the recycling importance of SCG in Turkey.

Implications: Coffee is a huge industry, and coffee has been widely used due to its refreshing properties. This industry generates large quantities of waste. Therefore, recycling of spent coffee grounds for producing alternative fuels and compounds of added value is crucial. Elemental analysis indicated that coffee waste can be utilized as compost, as it is rich in nitrogen. Coffee waste after oil extraction is an ideal feedstock for ethanol and biogas production, garden fertilizer, and as fuel pellets. The low degree of unsaturation provides excellent oxidation stability. Its biodiesel has also excellent cetane number, higher heating value, and lower iodine value.  相似文献   

176.
While Capparis spinosa var. herbaceace (2009) seeds collected from the Mardin-midyat region contains the highest protein (22.25 %), C. spinosa var. spinosa seeds (2009) collected from the Mu?la-Milas region contained the lowest protein (18.25 %). In addition, oil contents of C. spinosa and Capparis ovata seeds changed between 27.74 to 31.09 and 28.66 to 31.40 %, respectively. Crude cellulose contents of C. spinosa and C. ovata seeds were found as 28.24 and 29.67 %, respectively. It was found that ash content of C. spinosa and C. ovata seeds were found between 2.13 and 2.23 %, respectively. Phenolic matter content of C. spinosa and C. ovata were found between 1.98 mg (GAE) and 1.76 mg (GAE), respectively. Radical activity values of C. spinosa and C. ovata were determined as 83.432 and 83.718 %, respectively.  相似文献   
177.
In this study, we examined the ability of reflectance spectroscopy to predict some of the most important soil parameters for irrigation such as field capacity (FC), wilting point (WP), clay, sand, and silt content. FC and WP were determined for 305 soil samples. In addition to these soil analyses, clay, silt, and sand contents of 145 soil samples were detected. Raw spectral reflectance (raw) of these soil samples, between 350 and 2,500-nm wavelengths, was measured. In addition, first order derivatives of the reflectance (first) were calculated. Two different statistical approaches were used in detecting soil properties from hyperspectral data. Models were evaluated using the correlation of coefficient (r), coefficient of determination (R 2), root mean square error (RMSE), and residual prediction deviation (RPD). In the first method, two appropriate wavelengths were selected for raw reflectance and first derivative separately for each soil property. Selection of wavelengths was carried out based on the highest positive and negative correlations between soil property and raw reflectance or first order derivatives. By means of detected wavelengths, new combinations for each soil property were calculated using rationing, differencing, normalized differencing, and multiple regression techniques. Of these techniques, multiple regression provided the best correlation (P?<?0.01) for selected wavelengths and all soil properties. To estimate FC, WP, clay, sand, and silt, multiple regression equations based on first(2,310)-first(2,360), first(2,310)-first(2,360), first(2,240)-first(1,320), first(2,240)-first(1,330), and raw(2,260)-raw(360) were used. Partial least square regression (PLSR) was performed as the second method. Raw reflectance was a better predictor of WP and FC, whereas first order derivative was a better predictor of clay, sand, and silt content. According to RPD values, statistically excellent predictions were obtained for FC (2.18), and estimations for WP (2.0), clay (1.8), and silt (1.63) were acceptable. However, sand values were poorly predicted (RDP?=?0.63). In conclusion, both of the methods examined here offer quick and inexpensive means of predicting soil properties using spectral reflectance data.  相似文献   
178.
The concentrations of lead, cadmium and copper in roadside soil and plants in Elazig, Turkey were investigated. Soil samples were collected at distances of 0, 25 and 50 m from the roadside. The concentrations of lead, cadmium and copper were measured by Flame Atomic Absorption Spectrophotometry (FAAS). A slotted tube atom trap (STAT) was used to increase the sensitivity of lead and cadmium in FAAS. Lead concentrations in soil samples varied from 1.3 to 45 mg kg−1 while mean lead levels in plants ranged from120 ng g−1 for grape in point-4 to 866 ng g−1 for apple leaves in point-2. Lead analyses showed that there was a considerable contamination in both soil and plants affected from traffic intensity. Overall level of Cd in soil samples lies between 78 and 527 ng/g while cadmium concentration in different vegetations varied in the range of 0.8–98.0 ng g−1. Concentrations of copper in soil and plant samples were found in the range of 11.1–27.9 mg kg−1 for soil and 0.8–5.6 mg kg−1 for plants. Standard reference material (SRM) was used to find the accuracy of the results of soil analyses.  相似文献   
179.
Micro- and macro-element contents of several commercial fruit juices purchased from marked were determined by inductively coupled plasma atomic emission spectroscopy. Among the minor elements determined, Zn, Cu, Mn, Mo, Co, Cd and Ni were found to be lover. Major mineral contents of fruit juices were established as Ca, K, Mg and P. The potassium contents of fruit juices were determined at the higher levels. K contents of fruit juices ranged between 475 mg/kg (B apricot) and 1478 mg/kg (B peach). In addition while Ca contents of fruit juices change between 19.3 mg/kg (E cherry) and 81.8 mg/kg (C orange), Mg contents ranged at the levels between 23.7 mg/kg (A apricot) and 65.4 mg/kg (D orange). Generally Ca and contents of peach, orange and apricot juices that belong to A and D companies were determined at the high levels.  相似文献   
180.
Two honey samples are taken from two parts of the same honeycomb: one that contacts to the surface of the wire and the other taken from the surface that does not contact the wires. Heavy metal contents of these two samples were determined by inductively coupled plasma atomic emission spectrometry). The Mo, Cd, Cr, Fe, Mn, Ni and Zn contents of the honey in contact with wire is higher when compared to the other. Especially, Fe and Zn contents of honey in contact with wire is much higher than the non-contact one. These values are, respectively, 190.21 and 112.76 ppm. Besides, Ni content of honey in contact with wire is approximately 50% higher.  相似文献   
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