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Palaeo‐Mesoarchean Banded Iron formations (BIFs) of central Bundelkhand greenstone belts occur from Babina (in the west) to Mahoba (in the east) via Mauranipur along with the E–W trending of the Bundelkhand Tectonic Zone (BTZ). In the present study, we report petrological, geochemical, and mineralogical data of BIFs from the Babina, Mauranipur, and Mahoba greenstone belts of central Bundelkhand Greenstone Complex to address their source characteristics and deposition environment. The lithological association of BIFs in the Babina and Mauranipur greenstone belts consists of pillowed basic–ultrabasic volcanics and metasediments, whereas in the Mahoba greenstone belt, BIFs and quartzite occur within basic volcanics. These lithological associations collectively suggest that the entire succession was deposited in a marine environment. Based on geological setting, they are classified as Algoma‐type. The main mineral assemblages of the Babina and Mauranipur BIFs are composed of magnetite, quartz, ±garnet, hornblende, chlorite, and apatite, whereas the Mahoba BIFs along with magnetite and quartz, poised of two distinct mineral assemblages; the first one is Opx–Cpx–Grt and the other one is Grt–Hbl. The preliminary P–T study of these BIFs implies that they had gone through amphibolite‐ to granulite‐facies metamorphism. The geochemical characteristics show that BIFs from the Babina and Mauranipur greenstone belts are dominated by higher quartz and magnetite (total content = 90.63–99.95 wt.%), whereas the Mahoba greenstone belt is characterized by lesser quartz and magnetite components (total content = 86.68–94.58 wt.%). The PAAS (Post Archean Average of Australian Sediments)‐normalized REE patterns display significant positive Eu anomaly (Eu/Eu* up to 2.50) with well‐represented negative Ce anomalies (Ce/Ce* = 0.27–1.20). The REE and trace element ratios of BIFs from the Babina and Mauranipur greenstone belts suggest that they were formed by high‐T hydrothermal fluid activity without or very less continental input. Moreover, the Mahoba greenstone belt BIFs are formed by low‐T hydrothermal fluid activity with substantial continental input. Their chemical variation suggests the shallowing of the proto‐basin from the Babina in the west to Mahoba in the east. Tectonic discrimination plots imply the BIFs of the Babina, Mauranipur, and Mahoba greenstone belts of the central Bundelkhand Greenstone Complex are formed in a back‐arc tectonic setting. [ABSTRACT FROM AUTHOR]

The Compostela area is located in the western Trans‐Mexican Volcanic Belt, which consists of volcanic rocks that produced during the Pliocene to Recent volcanism. In this paper, we present petrography, whole‐rock major‐ and trace‐element concentrations, Ar–Ar ages, and Sr–Nd isotopic data of volcanic rocks from the Compostela area in the south of the city of Tepic, Nayarit, Mexico. These volcanic rocks are of intermediate composition and belong to the transitional series: basaltic trachyandesites [52.72–53.94 wt% SiO2; 0.69–2.53 wt% MgO] and subalkaline series: low‐Si [55.11–60.94 wt% SiO2; 0.79–2.74 wt% MgO] and high‐Si [61.60–62.71 wt% SiO2; 0.36–0.80 wt% MgO] andesites. The 40Ar/39Ar dating of two basaltic trachyandesites yields plateau ages of 1.05 ± 0.15 Ma and 1.07 ± 0.17 Ma and the andesites yielded a plateau age of 2.42 ± 0.36 Ma. These results indicate that the studied rocks were formed during the Pleistocene in two discrete episodes. The basaltic trachyandesites show enriched light rare earth elements patterns relative to high rare earth elements [(La/Yb)N = 5.81–8.07] with negligible Eu anomalies. The andesites display enriched large‐ion lithophile elements (Ba, K) with anomalies of Nb (Th/Ce) and Ti in the three groups identified in the subalkaline series. The basaltic trachyandesites appear in a tight cluster of initial 87Sr/86Sr ratios (0.703519–0.703882) as compared to the basaltic andesite 87Sr/86Sr (0.704073) and positive ɛNd(t) values of +5.6 to +3.4, respectively, indicating that the basaltic trachyandesites were derived from intermediate magmas from a shallow mantle source. Geochemical modelling reveals that both basaltic trachyandesite and andesite rocks were derived by a process of crystal fractionation accompanied by assimilation of crustal rocks at the lower or middle level. Geochemical ratios and multidimensional discrimination diagrams, combined with the cross‐section of the subduction zone indicates that basaltic trachyandesites were generated from a rift and/or Ocean Island Basalt‐type source, whereas andesites were generated from a slab‐derived source in a subduction environment. [ABSTRACT FROM AUTHOR]

The Mesa Virgen Calerilla (MVC) is located in the state of Zacatecas, Mexico. The most intense volcanism, which occurred during the Eocene, formed extensive ignimbrite deposits exposed in some parts as lava spills of rhyolitic (felsic) composition. This felsic volcanism may represent much of the MVC. This study describes whole‐rock geochemistry and mineralogy data from felsic volcanic rocks in the MVC to address their petrogenesis and tectonic setting. The MVC covers a compositional spectrum ranging from trachyte, dacite, to high‐silica rhyolite. The petrography and mineral assemblages indicate that the felsic rocks are composed of K‐feldspar (sanidine), quartz, plagioclase, and biotite. The felsic volcanic rocks have a composition of 64.08–78.17 wt% (SiO2)adj, 0.14–0.69 wt% (TiO2)adj, and 0.11–0.62 wt% (MgO)adj with 12–54 Mg number [Mg# = 100 × (Mg2+/[Mg2+ + Fe2+])]. These felsic volcanic rocks showed enrichment in light rare earth elements (LREE; [La/Sm]N = 3.80–7.19), and are depleted in heavy rare earth elements [HREE; (Tb/Yb)N ratios 0.35–1.84], along with negative Ba, Nb, Sr, P, Eu, and Ti anomalies. The geochemical characteristics and petrogenetic modelling indicate that felsic volcanic rocks are derived from partial melting process of an upper‐middle continental crust. The tectono‐magmatic model and multidimensional tectonic discrimination diagram indicate that an extensional‐related setting prevails for the MVC. [ABSTRACT FROM AUTHOR]

The Salina Cruz and Puerto Ángel beach areas in the Gulf of Tehuantepec, Mexican Pacific coast represent an important economic sector of the region. In this study, the mineralogy and geochemistry of bulk sediments, and geochronology of 400 detrital zircons recovered from the beach sediments were analysed to investigate their origin. The sediments are abundant in quartz, feldspar, ilmenite, cordierite, aragonite and anorthite. The chemical index of weathering revealed a moderate to intense weathering in the source area. The chondrite normalized REE patterns of bulk sediments are similar to the found in the Upper Continental Crust, suggesting the derivation of sediments from felsic igneous rocks. The REE patterns of zircons and the trace elemental ratios reveal a continental crust origin. Zircon U–Pb ages in the Salina Cruz beach were represented by Proterozoic (~545.1–1314.1 Ma; n = 170) and Cenozoic (~0.01–66 Ma; n = 20). The Puerto Ángel beach was abundant in Proterozoic zircon grains (~600.9–1171.4 Ma; n = 109) and followed by Mesozoic grains (~73.78–246.9 Ma; n = 40). The comparison of zircon U–Pb ages of this study with probable source rocks reveals that the Oaxaquia Terrane and Chiapas Massif Complex were the major contributors of Proterozoic zircons to the coastal areas. Similarly, the results indicate that the Cenozoic zircons were contributed by the Chiapas Massif Complex, coastal batholith and Cuicateco Terrane. The Mesozoic zircons are very few, derived from the nearby Xolapa Complex and the Chuacús Terrane. [ABSTRACT FROM AUTHOR]

The Goochland Terrane is an enigmatic crustal block in the Appalachian Piedmont Province of central Virginia, USA. Sparse exposures of terminal Mesoproterozoic and late Neoproterozoic igneous rocks in the central Goochland Terrane offer the opportunity to investigate both the continental affinity of the terrane during the Proterozoic Eon and the timing and mechanisms of crustal growth. We apply multiple geochemical tools to these rocks: tectonic discrimination using whole-rock major and trace element abundances; whole-rock Sm-Nd isotopes; O, U-Pb, and Lu-Hf isotope analyses of spots in zircon; and measurement of O isotopes in multi-grain quartz separates. Eruption of the Sabot Amphibolite protolith is difficult to date, but we tentatively assign an age of 552 ± 11 Ma. Goochland Terrane continental crust first separated from the mantle prior to ca. 1050–1010 Ma intrusion of the Montpelier Anorthosite and the State Farm Gneiss protolith. The granitic magma that became the State Farm Gneiss protolith could have been derived entirely from partial melting of this initial Goochland Terrane crust. In contrast, the magmas that became the Montpelier Anorthosite, Neoproterozoic granitoid, and the Sabot Amphibolite were mixtures of mantle melt and preexisting Goochland Terrane crust. This production of juvenile continental crust occurred during continental extension and, eventually, rifting. The timing and compositions of terminal Mesoproterozoic magmatism in the Goochland Terrane closely match those in the nearby Blue Ridge Province. Although the compositions of the Neoproterozoic magmas in the two regions are similar, intrusion and possibly eruption occurred about 10 M.y. later in the Goochland Terrane. [ABSTRACT FROM AUTHOR]

Highlights • There are sanukitoids and anatectic granites in the Bundelkhand Craton. • U-Pb zircon dating of a sanukitoid yielded a crystallization age of 2577 ± 16 Ma. • Sanukitoids are derived from a crustal source. • Sanukitoids and anatectic granites formed in a subduction-collision environment. Abstract In this paper, we present in situ zircon U–Pb ages as well as whole-rock elemental and Sm-Nd isotopic compositions for late Archean sanukitoids of the Bundelkhand Craton, India. The LA–ICP–MS zircon U–Pb dating results of the sanukitoids (s.l.) indicate that these rocks were emplaced at 2577 ± 16 Ma, with inherited zircon at an age of 2644 ± 25 Ma, and are coeval with high-K anatectic granites (2544–2583 Ma). The sanukitoids (s.l.) are characterized by high-alumina (15–16 wt.%), Mg# (27–50) and TiO 2 (0.31–0.87 wt.%). They have a strongly enriched signature in terms of incompatible trace elements (LREEs and LILE) pointing to a subduction-related or crustal source. The high-K anatectic granites are characterized by Al 2 O 3 (12–15 wt.%), Mg# (13–39) and TiO 2 (0.06–0.8 wt.%); they have enriched and variable concentrations of LILEs and REEs; and negative Eu anomalies (Eu/Eu* = 0.15–0.93). The whole-rock ε Nd (t) values (−3.64 to −1.66) indicate a crustal component. These isotopic and geochemical characteristics indicate that the sanukitoid plutons originated from the mixing of metasomatized mantle melts with anatectic melts and were followed by homogenization at shallow levels of emplacement, whereas the high-K anatectic granites indicate reworking of the pre-existing TTG crust during the cratonic stabilization ca. 2.5 Ga. This interpretation suggests a temporal evolution from TTG-domination through sanukitoids (s.l.) to anatectic leucogranites by an internal reworking of the continental crust, involving subduction-collision environments in the late Archean era. Such magmatic events and tectonics during the late-Archean in the Bundelkhand Craton resemble other Archean cratons, such as the Dharwar, North China, Karelian, Superior Province, Pilbara, Kaapvaal and Amazonian. [ABSTRACT FROM AUTHOR]

We applied both the ordinary linear regression (OLR) and the new uncertainty weighted linear regression (UWLR) models for the calibration and comparison of a XRF machine through 59 geochemical reference materials (GRMs) and a procedure blank sample. The mean concentration and uncertainty data for the GRMs used for the calibrations (Supplementary Materials) (available here) filewere achieved from an up-to-date compilation of chemical data and their processing from well-known discordancy and significance tests. The drift-corrected XRF intensity and its uncertainty were determined from mostly duplicate pressed powder pellets. The comparison of the OLR (linear correlation coefficient r∼0.9523–0.9964 and 0.9771–0.9999, respectively, for before and after matrix correction) and UWLR models (r∼0.9772–0.9976 and 0.9970–0.9999, respectively) clearly showed that the latter with generally higher values of r is preferable for routine calibrations of analytical procedures. Both calibrations were successfully applied to rock matrices, and the results were generally consistent with those obtained in other laboratories although the UWLR model showed mostly narrower confidence limits of the mean (slope and intercept) or lower uncertainties than the OLR. Similar sensitivity (∼2.69–46.17 kc·s−1·%−1 for the OLR and ∼2.78–59.69 kc·s−1·%−1 for the UWLR) also indicated that the UWLR could advantageously replace the OLR model. Another novel aspect is that the total uncertainty can be reported for individual chemical data. If the analytical instruments were routinely calibrated from the UWLR model, this action would make the science of geochemistry more quantitative than at present. [ABSTRACT FROM AUTHOR]

With respect to the adverse effects of chemical fertilizers on the environment and their higher cost, an alternative method of improving soil fertility has been tested. Application of vermicompost (VC) (produced from de-oiled waste) along with efficient bioinoculants (nitrogen fixer: Bacillus sp., JN700924; phosphate solubilizer: Bacillus megaterium, ATCC 14581; plant growth promoter: Pseudomonas monteilii, HQ 995498; arbuscular mycorrhizal fungus (AMF): Glomus intraradices) in different combinations were evaluated on Ocimum basilicum. VC along with bioinoculants-treated plots showed a significant improvement in biomass (15.1-56%), essential oil content (26.7-48.2%), and essential oil yield (44.7-108.4%) over control. The major constituent of essential oil (i.e., methyl chavicol) was significantly improved in T3 (VC + Bacillus sp.), T5 (VC + P. monteilii), and T6 (VC + G. intraradices) treated plants as compared to control (T1). Significant improvement in microbial counts, percent root colonization of AMF, and alkaline phosphatase activity were recorded; maximum in bioinoculants along with VC-treated plots. Improvement in soil organic carbon (4.2-51.16%), NH4+-N (27.0-55.3%), NO3--N (−8 to 60.33%], available P (15.2-43.5%), and available K (0.4-20.8%) were found in VC along with bioinoculants-treated plots. The diethylene triamine pentaacetic acid extractable Fe (109-154 mg kg−1 soil) was more influenced by VC along with bioinoculants than other micronutrients (Cu, Mn, and Zn). The results suggest that an integrated use of VC with bioinoculants improves soil health and essential oil yield of O. basilicum. [ABSTRACT FROM AUTHOR]

The central Bundelkhand greenstone complex in Bundelkhand craton, northern India is one of the well exposed Archaean supracrustal amphibolite, banded iron formation (BIF) and felsic volcanic rocks (FV) and associated with grey and pink porphyritic granite, tonalite–trondhjemite–granodiorite (TTG). Here we present high precision zircon U–Pb geochronological data for the pinkish porphyritic granites and TTG. The zircons from the grey-pinkish porphyritic granite show three different concordia ages of 2531 ± 21 Ma, 2516 ± 38 Ma, and 2514 ± 13 Ma, which are interpreted as the best estimate of the magmatic crystallization age for the studied granites. We also report the concordia age of 2669 ± 7.4 Ma for a trondhjemite gneiss sample, which is so far the youngest U–Pb geochronological data for a TTG rock suite in the Bundelkhand craton. This TTG formation at 2669 Ma is also more similar to Precambrian basement TTG gneisses of the Aravalli Craton of north western India and suggests that crust formation in the Bundelkhand Craton occurred in a similar time-frame to that recorded from the Aravalli craton of the North-western India. [ABSTRACT FROM AUTHOR]

Multidimensional discrimination diagrams (2006–2011) for basic and ultrabasic igneous rocks were applied to Precambrian rock suites from the Amazonian and São Francisco cratons, and the Tocantins Province, Brazil, to infer their possible tectonic settings. The chosen study cases in the Amazonian craton include the ca. 3.0 Ga metabasalts of the Identidade greenstone belt, 1.87–1.80 Ga Parauapebas anorogenic basalt-rhyolite dikes, 1.86–1.82 Ga Rio Branco anorogenic gabbro-basalt association, ca. 1.76–1.74 Ga Aripuanã and Teles Pires intracratonic basalt-felsic volcanic associations, and 1.76–1.74 Ga Jamari and 1.60–1.53 Ga Serra da Providência arc-related gabbroic rocks. In the São Francisco craton, we selected 1.48 Ga arc-related amphibolites of the Rio Capim greenstone belt, continental mafic dikes of Uauá (2.6 Ga), Curaçá and Chapada Diamantina (1.5 Ga), and Espinhaço (ca. 1.0 Ga). In the Tocantins Province, ca. 3.0 Ga komatiites associated with oceanic basalts of the Crixás and Guarinos greenstone belts were studied. The application of the diagrams generally provided consistent results with the authors’ proposed tectonic settings based on field relationships and geochemical data. The exceptions are some within-plate (continental) mafic dikes and basalts for which our diagrams do not work well. For comparison, we also used two ternary and two bivariate traditional discrimination diagrams for the data from the Amazonian craton, whose results were poorer than the newer multidimensional diagrams. [ABSTRACT FROM AUTHOR]

Fifty-five new multi-dimensional diagrams, mostly based on log-ratio transformations, were used to decipher tectonic settings for 17 cases of Precambrian belts in Canada, the USA, Poland, Finland, Jordan, Democratic Republic of Congo and Zambia, China, and India. The results of different sets of diagrams for basic-ultrabasic, intermediate, and acid magmas were generally internally consistent. Possible reasons for some inconsistencies may be related to the use of a sample group of mixed ages because of their uncertainties, extreme element mobility caused by metamorphism especially of high-grade type, analytical data quality, different petrogenetic processes for basic to acid magmas such as mantleversuscrustal origin, and some deficiencies that still exist in the multi-dimensional diagrams. To partly overcome the last problem, one new multi-dimensional diagram is proposed and used to discriminate mid-ocean ridge and oceanic plateau settings. [ABSTRACT FROM AUTHOR]

Andrographis paniculata Nees is an annual erect herb with wide medicinal and pharmacological applications due to the presence of andrographolide and other active chemical constituents. The large-scale cultivation of the kalmegh is not in practice. The aim of this study was to establish sustainable production systems of A. paniculata cv CIM-Megha with the application of different bioinoculants and chemical fertilisers. A. paniculata herb and andrographolide yield in the dried leaves was found to be highest (218% and 61.3%, respectively) in treatment T3 (NPK+Bacillus sp.) compared with T1 (control). The soil organic carbon, soil microbial respiration, soil enzymes activity and available nutrients improved significantly with combined application of bioinoculants and chemical fertilisers. [ABSTRACT FROM AUTHOR]

Fly ash (FA), a residue of coal combustion, has been accepted as a hazardous solid waste all over the world. Even though several approaches for its utilization in agriculture and material industry have been proposed, the amount of the stocked FA is increasing because production exceeds the amount that can be utilized. We propose the use of aromatic grasses for better in situ remediation of FA landfill hazards and to get several tangible and intangible benefits. [ABSTRACT FROM AUTHOR]

Although for ultrabasic and basic magmas a plethora of tectonomagmatic diagrams have been used, with the exception of one bivariate diagram for refined tectonic setting of orogenic andesites, none is available for highly abundant intermediate magma. We present 3 sets of discrimination diagrams obtained from the correct statistical methodology of loge-ratio transformation and linear discriminant analysis. All major element loge-ratio variables in 3664 samples, only immobile major and trace element loge-ratio variables in 1858 samples, and immobile trace element loge-ratio variables in 1512 samples were used. These diagrams with probability-based tectonic field boundaries and high success rates (about 69%-96%, 63%-100%, and 64%-100%, respectively, for diagrams based on all major elements, immobile major and trace elements, and immobile trace elements) were first tested for fresh and highly altered rocks. The expected tectonic setting was indicated from our diagrams. The probability-based decisions and total percent probability estimates can fully replace the actual plotting of samples in the diagrams. The probability calculations were then used for tectonic discrimination of 7 case studies of Archean to Proterozoic rocks. An island arc setting was indicated for the Wawa greenstone belt (Canada), implying the existence of plate tectonic processes during the Late Archean, for western Tasmania (Australia) during the Cambrian, and for Chichijima Island (Bonin Islands, Japan) during the Eocene. Similarly, an arc setting (indecisive island or continental type) was obtained for south-central Sweden during the Paleoproterozoic and for Adola (southern Ethiopia) during the Neoproterozoic. A within-plate setting was inferred for the Neoproterozoic Malani igneous complex, Rajasthan, India. A collision setting was indicated for the Alps (France-Italy-Switzerland) during the Late Carboniferous. Modeling of likely as well as extreme processes indicates that these diagrams are robust against postemplacement compositional changes caused by analytical errors, element mobility, Fe-oxidation, alteration, and petrogenetic processes. [ABSTRACT FROM AUTHOR]

Abstract: Kalmegh (Andrographis paniculata Wall. ex Nees) is a medicinal herb of tropical south east Asia and native to India and Sri Lanka. It has been used herb for liver ailment in all prevailing systems of medicine viz. Ayurvedic, Unani, Homeopathic and modern throughout most of the south East Asian countries viz. China, India, Sri Lanka, Indonesia, Thailand, Burma, and Vietnam, etc. Commercially cultivation of Kalmegh is done through seeds. Optimal germination potential, temperature and first as well as final count day are three primary parameters for developing the seed quality standards. Germination of Kalmegh variety ‘CIM-Megha’ was carried out at six constant temperatures at an interval of every ‘5°C’ from ‘15 to 40°C’ temperatures coupled with 16h light and 8h dark photo period. The temperature of ‘25°C’ was found optimally suitable with ‘94.6’ and ‘23.6’ percentage of germination and germination energy, respectively, while the temperature at ‘40°C’ was deleterious with no germination. Significant decrease in percentage of germination and germination energy was observed at ‘15°C’, ‘20°C’, ‘30°C’ and ‘35°C’ of temperature in comparison to ‘25°C’. The study further revealed that days 5-6 and days 7-9 after seed sowing were the ideal for first and final count, respectively for seed germination of Kalmegh. [Copyright &y& Elsevier]

Abstract: Palmarosa (Cymbopogon martinii) is a major essential oil bearing crop commercially cultivated in India. However, the potentiality of its commercial cultivation is restricted due to the supply of poor quality seed material, i.e. poor seed germination percent/vigour and lack of knowledge about the seed rate for nursery raising/direct sowing and viability period under storage conditions. Seed germination tests of varieties PRC-1, Trishna, Tripta, Vaishnavi were carried out in Petri plates under two temperature regimes: uncontrolled, i.e. room temperature (average minimum 27°C–average maximum 39°C) and controlled and constant (15°C, 20°C, 25°C with 16h light and 8h dark photoperiod). Maximum germination percentage and germination energy percent were recorded in ‘Trishna’ (34.25 and 8.56), followed by ‘PRC-1’ (34.25 and 8.56), ‘Tripta’ (15.75 and 3.94) and ‘Vaishnavi’ (10.25 and 2.56) on final count day at controlled and constant temperature. The corresponding data were recorded (26.00 and 6.50), followed by (25.50 and 6.37), (9.50 and 2.37) and (10.00 and 2.50) under uncontrolled temperature. Differential behavior of the said varieties under different temperature regimes was attributable to their genetic make-up. Results showed that day 2 and days 3–4 was the best for first count, day 5 and days 6–7 for final count and day 5 and days 6–7 for germination period at uncontrolled and controlled and constant temperature, respectively. [ABSTRACT FROM AUTHOR]

The Pinos Volcanic Complex (PVC) is located in the San Luis Potosi Volcanic Field (SLPV) and southern region of the Mesa Central that includes Oligocene rhyolites and trachydacites. These felsic volcanic rocks are characterized by porphyritic textures with a main mineralogical arrangement of phenocrystals of quartz, potassium feldspar (sanidine), plagioclase and biotite embedded in a vitreous matrix with microcrystals of quartz. They display peraluminous, high-silica, alkaline (not peralkaline) composition, with flat heavy rare earth element concentrations and negative Eu anomalies values. They are enriched in large-ion lithophile elements (LILEs; Rb, Ba, K, Th, Ce) relative to highfield-strength elements (HFSE; Nb, Zr, P, Ti). Trace element ratios trend highlights variable degree of partial melting rather than the role of fractional crystallization. The petrogenetic modelling of trace elements reveal that the felsic volcanic rocks are consistent with their formation via partial melting of the middle/upper continental crust. Multi-dimensional tectonic discriminant diagrams and magmatic model indicate an extensional tectonic environment for the genesis of the felsic volcanic rocks. • The PVC is represented by mainly felsic volcanic rocks. • Partial melting of the middle-upper continental crust generated the felsic volcanic rocks. • Magmatic events occurred in the PVC during middle Oligocene in an extensional regime. [ABSTRACT FROM AUTHOR]

The article talks about geochemistry as an aiding tool to understand tectonic setting of igneous rocks associations, but continental mafic dykes and flood basalts are targets that even geochemical discrimination diagrams fail to correctly classify. It talks of this paradox explained through crustal contamination, degree of mantle melting and mantle source characteristics. It also makes a mention of plotting geochemical data for key continental mafic dyke swarms in multi-dimensional diagrams.

The article focuses on the use of aromatic plants in phytoremediation as a sustainable method for the remediation of sites polluted with heavy metals. It states that soil remediation of heavy metals using conventional technologies requires a significant capital cost. It comments on the benefits of using aromatic plants as suitable phytoremediation candidates and the risks related to non-aromatic edible crops. It talks about the use of aromatic plants in essential oils and food processing.

Andrographis paniculata is a source of diterpenoids and 2′-oxygenated flavonoids, which are of utility in pharmaceutical industry and ayurvedic formulations. With the aim of producing quality herb, an experiment was conducted with different combinations of bio-inoculants and vermicompost (VC) in controlled condition. It was observed that the highest Leaf:Stem (L:S) ratio, fresh herb yield and andrographolide yield (0.82, 300 g pot −1 and 29.8 g kg −1 dry herb, respectively) was recorded when the soil was incorporated with VC along with Azotobacter chrococcum (T 3 ). Further there was a significant improvement in all soil fertility parameters. However, when all the bio-inoculants ( A. chrococcum + Bacillus megaterium + Pseudomonas monteilii + Glomus intraradices ) were mixed with VC, there was a significant improvement in soil dehydrogenase, alkaline, and acidic phosphatase activity. A positive correlation coefficient ( p < 0.01) could be derived amongst plant growth, yield and soil properties ( r = 0.45–0.85). The study suggests that application of the bio-inoculants and organic fertilizers can enhance productivity while maintaining the desired quality of the herb. [ABSTRACT FROM AUTHOR]

Natural catalysts are important for the low-cost and large-scale production of carbon nanostructures. In this study, we used a natural material obtained from thin bands of sedimentary rocks known as Banded Iron Formation (BIF). BIF powders (pristine and ball-milled) were used as catalysts for the large-scale production of nitrogen-doped multi-walled carbon nanotubes (N-MWCNTs) via an aerosol-assisted catalytic chemical vapor deposition (AACCVD) experiment. The morphology and composition profiles of the BIF powders and N-MWCNT samples were analyzed by scanning and transmission electron microscopies, X-ray diffraction, X-ray photoelectron (XPS) and Raman spectroscopies, and thermogravimetric analysis. XRD characterizations revealed that the BIF powders were mainly composed of quartz and hematite. This result was also confirmed by Raman spectroscopy. The production efficiency of 340% wt./wt. of the N-MWCNTs was obtained by 1 h ball-milled BIF powders. The specific surface area of the N-MWCNTs reached 37.87 m2/g. The type of nitrogen doping, oxygen functional groups, silicon, and carbon species (sp2 and sp3) hosted at the surface of the N-MWCNTs were quantified by XPS. The electrochemical response of electrodes composed of the N-MWCNTs were studied via cyclic voltammetry, electrochemical impedance, and coulombic efficiency determination to assess the possible applications of our synthesized materials as energy storage or sensor systems. The magnetic properties and effects of acid and thermal treatments on the morphology of the N-MWCNTs are also presented. • Facile route to produce high yield of nitrogen-doped carbon nanotubes using natural catalyst. • SiO 2 –Fe 3 O 2 new natural material as catalyst interacting with nitrogen molecules for enhanced yield of nanocarbons. • Competitive surface area in pristine nitrogen-doped carbon nanotube. • Produced N-MWCNTs could be used as electrodes in energy storage and sensor systems. [ABSTRACT FROM AUTHOR]