Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0205700 (ash)
 15,125 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Environment has significant effects on the nutrient content of field-grown crop plants. Little is known, however, about compositional changes caused by controlled environments in which plants receive only artificial radiation and soilless, hydroponic culture. This knowledge is essential for developing a safe, nutritious diet in a Controlled Ecological Life-Support System (CELSS). Three crops that are candidates for inclusion in a CELSS (rice, wheat, and white potato) were grown both in the field and in controlled environments where the hydroponic nutrient solution, photosynthetic photon flux (PPF), and CO2 level were manipulated to achieve rapid growth rates. Plants were harvested at maturity, separated into discrete parts, and dried prior to analysis. Plant materials were analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate, minerals, and amino-acid composition. The effect of environment on nutrient content varied by crop and plant part. Total N and nonprotein N (NPN) contents of plant biomass generally increased under controlled-environment conditions compared to field conditions, especially for leafy plant parts and roots. Nitrate levels were increased in hydroponically-grown vegetative tissues, but nitrate was excluded from grains and tubers. Mineral content changes in plant tissue included increased phosphorus and decreased levels of certain micronutrient elements under controlled-environment conditions. These findings suggest that cultivar selection, genetic manipulation, and environmental control could be important to obtain highly nutritious biomass in a CELSS.
 ...
PMID:Excess nutrients in hydroponic solutions alter nutrient content of rice, wheat, and potato. 1153 17

Two methods of extracting mineral elements from otherwise deadlock products of a life-support system are presented. We describe first optimum conditions for recovering elements by water extraction from dry wastes of plants, biomass ash, and solid human wastes after passing them through the catalytic furnace; and, second, we describe acid extracts of biogenous elements by 1N and 2N HNO3 from these products. Ways to use the extracts of elements in plant nutrition are considered in order to increase the extent to which the mineral loop of a life-support system can be closed.
 ...
PMID:Extraction of mineral elements from inedible wastes of biological components of a life-support system and their utilization for plant nutrition. 1153 19

Tomato (Lycopersicon esculentum Mill.) cvs. Red Robin (RR) and Reimann Philipp (RP) were grown hydroponically for 105 d with a 12 h photoperiod, 26 degrees C/22 degrees C thermoperiod, and 500 micromol m-2 s-1 PPF at either 400, 1200, 5000, or 10,000 micromol mol-1 (0.04, 0.12, 0.50, 1.00 kPa) CO2. Harvested fruits were analyzed for proximate composition, total dietary fiber, nitrate, and elemental composition. No trends were apparent with regard to CO2 effects on proximate composition, with fruit from all treatments and both cultivars averaging 18.9% protein, 3.6% fat, 10.2% ash, and 67.2% carbohydrate. In comparison, average values for field-grown fruit are 16.6% protein, 3.8% fat, 8.1% ash, and 71.5% carbohydrate (Duke and Atchely, 1986). Total dietary fiber was highest at 10,000 micromol mol-1 (28.4% and 22.6% for RR and RP) and lowest at 1000 micromol mol-1 (18.2% and 15.9% for RR and RP), but showed no overall trend in response to CO2. Nitrate values ranged from 0.19% to 0.35% and showed no trend with regard to CO2. K, Mg, and P concentrations showed no trend in response to CO2, but Ca levels increased from 198 and 956 ppm in RR and RP at 400 micromol mol-1, to 2537 and 2825 ppm at 10,000 micromol mol-1. This increase in Ca caused an increase in fruit Ca/P ratios from 0.07 and 0.37 for RR and RP at 400 micromol mol-1 to 0.99 and 1.23 for RR and RP at 10,000 micromol mol-1, suggesting that more dietary Ca should be available from high CO2-grown fruit.
 ...
PMID:Effect of elevated carbon dioxide on nutritional quality of tomato. 1154 78

Five modifiers were tested for the direct determination of cobalt in coal fly ash and slag by ultrasonic slurry-sampling electrothermal atomic absorption spectrometry (USS-ETAAS). The furnace temperature programs and the appropriate amount for each modifier were optimized to get the highest signal and the best separation between the atomic and background signals. Nitric acid (0.5% v/v) was the most adequate chemical modifier for cobalt determination, selecting 1,450 degrees C and 2,100 degrees C as pyrolysis and atomization temperatures, respectively. This modifier also acts as liquid medium for the slurry simplifying the procedure. The remaining modifiers enhanced the background signal, totally overlapped with cobalt peak. The method optimized gave a limit of detection of 0.36 microg g(-1), a characteristic mass of 13 +/- 1 pg and an overall-method precision which is highly satisfactory (<7%, RSD). The method was validated by analyzing two certified coal fly ash materials, and satisfactory recoveries were obtained (83-90%) and no statistical differences were observed between the experimental and the certified cobalt concentrations. Additionally, certified sediment, soil and urban particulate matter were assayed; again good results were obtained. The developed methodology was used to determine cobalt in several coal combustion residues from five Spanish power plants.
 ...
PMID:Chemical modifiers for direct determination of cobalt in coal combustion residues by ultrasonic slurry-sampling-ETAAS. 1179 13

The strontium, lithium and calcium contents have been determined in 87 samples of five kinds of milk-fermented products, as well as in 93 samples of ten kinds of marine smoked fish. The samples were purchased on the local market. The representative samples were dry ashed in quartz crucibles and the ash was treated with suitable amounts of conc. HCl and a few drops of conc. HNO3. The obtained sample solution was then used for the determination of Sr, Li and Ca by the flame atomic absorption spectrometry (AAS) method. Ca and Li were determined using the air-acetylene flame and Sr with nitrous oxide-acetylene flame, according to the manufacturer's recommendations. The contents of Sr in the fermented milk products ranged from 0.21 to 0.79 (mean 0.44 +/- 0.07) and in the marine smoked fish from 0.02 to 4.63 (mean 1.16 +/- 0.24) mg/kg of the edible form of both products. Li contents in the milk products ranged from 0.01 to 0.50 (mean 0.07 +/- 0.04) and in the smoked fish from 0.00 to 0.58 (mean 0.11 +/- 0.08) mg/kg. The calcium was highest in the milk products and ranged from 1,010 to 2,020.0 (mean 1,377 +/- 143) mg/kg. In the smoked fish calcium varied strongly and ranged from 40 to 1,052 (mean 303 +/- 53) mg/kg of the edible form. The calculated average ratio of strontium to calcium (mg Sr/1 g Ca) in the milk beverages and yogurts amounted 0.32 and in the smoked fish was 12 times as high and amounted 3.84. The main purpose of this work was to present Ca, Sr and Li together. This is justified because Sr and to some extent also Li are able to modulate Ca metabolism and vice versa.
 ...
PMID:Content of strontium, lithium and calcium in selected milk products and in some marine smoked fish. 1210 23

A microwave digestion procedure for asphaltite ash was developed in an attempt to facilitate routine analysis and obtain reproducible conditions or comparable results. The conditions of the most effective procedure for 0.1 g asphaltite ash samples are 1 ml of HNO3 + 3 ml of HCl + 1 ml of HF + 1 ml of deionized water as acid mixture and 15 min for digestion time. The digestion was accomplished in five stages applying continuously 90% to 20% of the microwave power and 20 to 100 psi of the pressure for 10 min of total time. Concentrations of selected elements, Cr, Co, Fe, Mn, Ni and Zn were measured using inductively coupled plasma-atomic emission spectroscopy. The proposed method of digestion provided precise results with relative standard deviations generally less than 3% for investigated elements. Results for fly ash as standard reference material was in good agreement with certified values.
 ...
PMID:Comparison of microwave digestion procedures for the determination of some elements in asphaltite ash using ICP-AES. 1255 36

The chemical composition of snow and terricolous lichens was determined along transects through the Subarctic towns of Vorkuta (130 km west-east), Inta (240 km south-north) and Usinsk (140 km, southwest-northeast) in the Usa river basin, northeast European Russia. Evidence of pollution gradients was found on two spatial scales. First, on the Inta transect, northward decreases in concentrations of N in the lichen Cladonia stellaris (from 0.57 mmol N g(-1) at 90 km south to 0.43 mmol N g(-1) at 130 km north of Inta) and winter deposition of non-sea salt sulphate (from 29.3 to 12.8 mol ha(-1) at 90 km south and 110 km north of Inta, respectively) were attributed to long range transport of N and S from lower latitudes. Second, increased ionic content (SO42-, Ca2+, K+) and pH of snow, and modified N concentration and the concentration ratios K+:Mg2+ and K+: (Mg2++Ca2+) in lichens (Cladonia arbuscula and Flavocetraria cucullata) within ca. 25-40 km of Vorkuta and Inta were largely attributed to local deposition of alkaline coal ash. Total sulphate concentrations in snow varied from ca. 5 micromol l(-1) at remote sites to ca. 19 micromol l(-1) near Vorkuta. Nitrate concentration in snow (typically ca. 9 micromol l(-1)) did not vary with proximity to perceived pollution sources.
 ...
PMID:Regional variation in the chemical composition of winter snow pack and terricolous lichens in relation to sources of acid emissions in the Usa river basin, northeast European Russia. 1282 18

Major, minor and trace elemental contents in northeast China soybeans were determined by using inductively coupled plasma atomic emission spectrometry (ICP-AES). Three different sample digestion methods including two wet digestions, HNO3-HClO4 and HNO3-H2SO4 and a dry ash method were compared. Owing to the high oil content in soybeans, long time is needed and access acid should be added with mixed acid digestion methods, which may result in higher sample blank. Therefore, the dry ask method would be more proper for the pre-treatment of soybean samples. Potassium and phosphorus are major elements in soybeans, so the effect of potassium and phosphorus on the other elements was investigated. Results showed that the potassium and phosphorus did not affect the determination of other trace elements. There are not significant differences in trace elemental contents for the eleven northeast China soybeans.
 ...
PMID:[Major, minor and trace-elemental contents analysis in northeast soybeans by ICP-AES]. 1293 96

In HNO3 medium the fading reaction of arsenazo III oxidated with Cr2O7(2-) was used as to determine trace Cr in fly ash containing Cr. The results show that the fading reaction has high sensitivity in the medium of 3.2 mol.L-1 nitric acid, the molar absorptivity of 3.9 x 10(6) L.mol-1.cm-1 at 520 nm, and Beer's law is obeyed for Cr (VI) in the range of 0.0-40.0 micrograms.L-1. Contents of Cr in fly ash were determined with satisfactory results.
 ...
PMID:[Spectrophotometric determination of trace chromium in fly ash]. 1294 11

A new method is described for the analysis of whole coal for the major ash forming elements by ICP-AES. The major ash forming elements were extracted with HF and HNO3 in an ultrasonic water bathe. The best proportion of the acid and the time of extraction were studied. Compared with the ash content of coal, the extraction ratio is more than 95%. Recovery ratio is between 96%-104%. RSD of extraction and determination is less than 4% (n = 9).
 ...
PMID:[Acid extraction of coal for the determination of major ash forming elements by ICP-AES]. 1294 63


<< Previous 1 2 3 4 5 6 Next >>