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[en] The fruits of Indian jujube (Zizyphus mauritiana Lamk.) are commonly used as fresh. However, fresh fruits are vulnerable to decay after few days of picking due to high moisture content and thus need to be preserved through drying. Therefore, the current study was aimed to assess the effect of different drying methods on physico-chemical properties of fruits of various Indian jujube cultivars. Fruits of eleven cultivars were collected from Horticultural Research Station, Bahawalpur. Physical, organoleptic and biochemical attributes of the fruits were measured before drying. The drying treatments included were; sun dry, oven dry at 50 °C, oven dry at 60 °C and oven dry at 70 °C. Significantly greater (p = 0.05) fresh fruit weight was recorded in Dehli sufaid (29.61 g) and Pak white (29.58 g), while Dehli sufaid (6.02 g) followed by Pak white (5.94 g) also showed significantly greater fruit weight after drying. Significantly larger fruit length was measured in Sadqia (41.97 mm) before drying, while Umran-13 (34.94 mm) showed significantly larger fruit length after drying. Significantly larger fruit diameter was calculated in Pak white (37.11 mm), Dehli sufaid (36.85 mm) and Foladi (36.53 mm) before drying, while Pak white (20.68 mm) and Dehli sufaid (20.59 mm) exhibited significantly larger fruit diameter after drying. Significantly greater moisture contents were recorded in fresh fruits of Karella (82.99%), while Anokhi (20.95%) showed significantly greater moisture content after drying. Sensory evaluation revealed that fresh fruits of Yazman local had very good appearance and firmness, and were good after drying. Fruits of Mehmood wali had very liked color and taste before drying and liked after drying. Vitamin C contents were found significantly greater in fresh fruits of Akasha (72.51 mg/100 mL), while significantly greater vitamin C contents were in dried fruits of Sadqia (50.71 mg/100 mL). Drying methods were statistically significant for total phenolic content, and antioxidant activity and capacity. The maximum total phenolic content (305.40 µg GAE /mL) and antioxidant capacity (145.44 µM trolox/100 mL) were recorded in oven dried fruits at 70 °C. (author)
[en] This technical dictionary contains terms from soil and site science, as well as from overlapping disciplines such as agronomy, forestry, landscape planning, meteorology, geology, geomorphology, physical geography, botany, biochemistry, plant nutrition and fertilizer use, applied ecology, microbiology and technology. The terminology of the mentioned disciplines contains about 10,000 terms in German and English. Appendices include names of plants and animals, SI units, as well as tables of soil classification.
[de]Dieses zweisprachige Fachwörterbuch beinhaltet Begriffe der Wissensgebiete Bodenkunde und Standortlehre sowie ihrer Nachbardisziplinen Angewandte Ökologie, Land- und Forstwirtschaft sowie Landschaftsplanung. Die Terminologie der aufgeführten Wissensgebiete umfasst etwa 10.000 Begriffe in deutscher und englischer Sprache. Ein Anhang enthält Pflanzennamen, Tiernamen, SI-Einheiten und Begriffe der Bodenklassifikation. An Teildisziplinen der Bodenkunde werden Bodengeologie, Bodenmineralogie, Bodenphysik, Bodenchemie, Bodenbiologie, Bodenökologie, Bodentechnologie und Bodenschutz berücksichtigt. Ferner werden relevante Begriffe aus folgenden Nachbardisziplinen aufgeführt: Mineralogie, Petrographie, Geologie, Geomorphologie, Geographie, Meteorologie und Klimakunde, Botanik, Mikrobiologie, Biochemie, Pflanzenernährung und Düngung, Acker- und Pflanzenbau, Waldbau und Immissionsforschung. Der Wortumfang reicht aus, um die moderne Fachliteratur auf den Gebieten der Geo- und Biowissenschaften zu verstehen, soweit sie sich mit der Entstehung, Beschreibung, Gestaltung und Nutzung von Landschaften befasst. Die Übersetzungsarbeit wird dadurch erleichtert, dass den Substantiven jeweils relevante Adjektive zugeordnet sind.
[en] To analyze the recovery pattern of carbon pools in terms of size and the relative contribution of each pool to total ecosystem C along a fire chronosequence of tropical mixed pine-hardwood forest. Las Joyas Research Station (LJRS), core zone of Sierra de Manantlán Biosphere Reserve (SMBR) in the state of Jalisco, central western Mexico. Carbon stored in aboveground plant biomass, standing dead trees, downed woody debris, forest floor, fine roots and mineral soil, was compared with a nested analysis of variance (ANOVA) in post-fire stands of eight-year-old, 28- and 60-year-old stands of mixed Pinus douglasiana-hardwood forest. The total ecosystem carbon in eight-year-old stands was 50% lower than that of 60-year-old stands. Carbon content in the biomass and mineral soil increased with stand age. The carbon in the biomass recovered to the undisturbed forest in the 28 years of succession. The main C storage in the eight-year-old stands were the mineral soil (64%) and downed woody debris (18%), while in the 28- and 60-year-old stands, live tree biomass and mineral soil were the two largest components of the total C pool (43% and 46%, respectively). We found a significant effect of high-severity fire events on ecosystem C storage and a shift in carbon distribution. The relatively fast recovery of C in ecosystem biomass suggests that mixed Pinus douglasiana hardwood forest possess functional traits that confer resilience to severe fire events.
[en] During the late Neoproterozoic, the Salt Range in Pakistan was one of the regions where the Tethys truncated and marine strata developed. The numerous transgressions and regressions that occurred during that period provided enough initial material for the development of marine evaporites. The geology of the Salt Range is characterized by the presence of dense salt layers and the existence of four regional and local scale unconformities. These thick salt deposits geologically favor potash formation. Here we coupled chloride isotope geochemistry and classical chemistry of local halite samples to assess the extent of brine evaporation that ultimately formed the salt deposits. Our results indicate that evaporites in the Salt Range area are Br-rich and precipitated from seawater under arid climate conditions. The corresponding δ37Cl values vary from -1.04‰ to 1.07‰, with an average of -0.25‰ ± 0.52‰, consistent with the isotope range values reported for other evaporites worldwide. The positive δ37Cl values we obtained indicate the addition of nonmarine Cl, possibly from reworking of older evaporites, the influx of dilute seawater, the mixing of meteoric and seawater, and the influence of gypsum-dehydration water. The negative Cl isotope compositions (δ37Cl < -1‰) indicate that brines reached the last stages of salt deposition during the late Neoproterozoic. We conclude that the Salt Range Formation could be promising for K-Mg salts. (author)
[en] A combination of geochemical variables is necessary to explain the origin of life on Earth. Thus, in this work the sorption of Poly-A on a clay mineral (kaolinite) was studied to get an insight about the sorption capacity at different times and pH values, as well as to confirm the capabilities of the clay to protect the sorbate from an external source of ionizing radiation. Poly-A presented a high percentage of sorption in the clay, especially in acidic environments, and this percentage sharply decrease in alkaline media. On the other hand, Poly-A’s recovery was higher in the system with clay, confirming its protection role. (author)
[en] We present systematic U-Pb age data collected by laser ablation multi-collector inductively coupled plasma mass spectrometry, precise geochemical data, and Nd isotope data for igneous rocks from the southeastern Lesser Xing’an Range (SE LXR). The results indicate that the formation ages as follows: Maojiatun alkaline granite, 207.2 ± 0.84 Ma and 204.6 ± 0.93 Ma; Diorite porphyrite, 164.5 ± 0.97 Ma; and Tieli syenogranite, 186.7 ± 1.50 Ma. The alkaline granite has high silicon, potassium, alkali, and FeOT contents; it is enriched in high field strength elements, Zr, Hf, Th, Rb, and U; is depleted in Ba, Sr, Nb, Ta, P, Ti, etc.; and has high ratios of 10000Ga/Al. It shows an A2-type granite affinity. The Tieli alkali-feldspar granite has high total alkali contents and is enriched in high field strength elements and rare earth elements and depleted in Sr, Ba, Ti, and P, and shows varying degrees of alkalinity. Rocks from SE LXR display similar εNd (t) values with corresponding to Nd model ages of 1095 to 813 Ma. The igneous rocks from the SE LXR are proposed to be derived from melting of the Neoproterozoic lower crust and potential magma mixing with ancient crystalline basement. The formation of the Maojiatun alkaline granite occurred in response to a postorogenic event following the closure of the Paleo-Asian Ocean. However, the SE LXR exhibited an extensional back-arc tectonic setting in the Early Jurassic. The Middle Jurassic diorite porphyrite could be related to the temporary stagnation of the westward subduction of the Paleo-Pacific plate. (author)
[en] Two different types of igneous rock formed during separate Cenozoic magmatic phases in the Varan-Naragh area in the central part of the Urumieh-Dokhtar Magmatic Arc (UDMA) of Iran as a part of the Alpine-Himalayan system. The first phase comprises late Eocene - early Oligocene Naragh gabbroic rocks (Ns), and the second phase is characterized by the emplacement of both volcanic and plutonic rocks of the early Miocene. Both phases display moderate enrichment of large rare earth elements and depletion of high field strength elements coupled with negative Nb, Ti, and P anomalies, indicative of subduction-related magmatic events within an active continental margin. Initial values of 87Sr/86Sr and εNdT are 0.70684 and +0.15 and 0.70560- 0.70654 and +2.55 to +3.49 for Ns and early Miocene intrusive and volcanic rocks, respectively. Comparisons of rare earth element patterns and mantle-like isotopic ratios suggest that Ns mafic and early Miocene magmatic rocks were derived from partial melting of a common subcontinental lithospheric mantle. Geochemical and isotopic ratios of Ns gabbroic rocks, in combination with the data related to other coeval and proximal mafic-intermediate intrusions (such as Nashalj), suggest enrichment of the lithospheric mantle by slab-derived fluids with a minor subducted sediment melt. The low εNdT of Ns gabbroic rocks can reflect involvement of slab-derived components. The geochemical similarity and the close spatial and temporal association of Varan intrusive and volcanic rocks suggest a common petrogenetic relationship. Geochemical, isotopic, and geochronological evidence from the region indicate three major phases of igneous activity in the Kashan magmatic segment of the central UDMA during late Eocene to Miocene, resulting in complex tectonic regime transition from compressional subduction to extensional postcollisional settings. Integrated with published studies, the new results support a model suggesting that subduction-related magmatic activity was still influencing the central UDMA in the early Miocene time and are also consistent with the notion of oblique and diachronous collision along the northeast margin of the Arabia plate. (author)
[en] The ability of organic self-assembled monolayers (SAMs) to act as insulating barriers to electron transfer, ion transport, or molecular diffusion is critical to their application in a variety of technologies. The use of appropriate analytical tools to characterize the dielectric properties of these molecular thin films is important for the control of structural defects and establishing structure-property relations. In this context, we analyze the ionic permeability and dielectric response of SAMs formed from a homologous series of n-alkanethiolates (CH3(CH2)nS, where n = 9, 11, 13, 15, 17, and 19) on gold using the immittance quantities of the complex impedance, capacitance, and permittivity available from the same electrochemical impedance spectroscopy (EIS) measurement. The most sensitive parameters and frequency range for characterizing the capacitive behavior and assessing the ion-blocking quality of the SAMs under non-Faradaic conditions are identified. We also investigate the effect of chain length on the interfacial capacitance and dielectric constant of ionic insulating SAMs. The advantages of the capacitance quantity and related permittivity data over traditional impedance representations and equivalent electric circuit modeling are discussed. (author)
[en] The composition of hydrogen and hydrogen-methane plasmas containing ∼ 10% of BX3, SiX4, GeX4 (X = F, Cl), SF6, MoF6 and WF6 is calculated for the temperature range ∼ 300-4000 K using the equilibrium chemical model. The calculations provide valuable information about thermodynamic parameters (pressure, temperature) needed for condensation of pure elements (in H2 plasma) and their carbides (in H2 + CH4 plasma) and about intermediate reaction products. Using volatile fluorides for plasma chemical deposition alleviates obtaining monoisotopic elements and their isotopic compounds because fluorine is monoisotopic. PECVD is promising method for one-step conversion of fluorides to elemental isotopes and their carbides. For fluorides, further insight is needed into properties of plasmas supported by different types of discharges. (author)