The novelty of this research lies in the successful fabrication of a 3D-printed honeycomb structure filled with nanofillers for acoustic properties,utilizing an impedance tube setup in accordance with ASTM standard E ...The novelty of this research lies in the successful fabrication of a 3D-printed honeycomb structure filled with nanofillers for acoustic properties,utilizing an impedance tube setup in accordance with ASTM standard E 1050-12.The Creality Ender-3,a 3D printer,was used for printing the honeycomb structures,and polylactic acid(PLA)material was employed for their construction.The organic,inorganic,and polymeric compounds within the composites were identified using fourier transformation infrared(FTIR)spectroscopy.The structure and homogeneity of the samples were examined using a field emission scanning electron microscope(FESEM).To determine the sound absorption coefficient of the 3D printed honeycomb structure,numerous samples were systematically developed using central composite design(CCD)and analysed using response surface methodology(RSM).The RSM mathematical model was established to predict the optimum values of each factor and noise reduction coefficient(NRC).The optimum values for an NRC of 0.377 were found to be 1.116 wt% carbon black,1.025 wt% aluminium powder,and 3.151 mm distance between parallel edges.Overall,the results demonstrate that a 3Dprinted honeycomb structure filled with nanofillers is an excellent material that can be utilized in various fields,including defence and aviation,where lightweight and acoustic properties are of great importance.展开更多
We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc widt...We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc width and mass. Our preliminary results are: M(ηc) = 2979.4± 1.5 ± 1.9 MeV/c^2, Г(ηc) = 27.8±5.1 ±3.3 MeV, B(Jψ→ηcγ) = (2.34±0.15±0.40)%.展开更多
This paper addressed the efect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method.Anthracite was impregnated with 5 wt%of...This paper addressed the efect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method.Anthracite was impregnated with 5 wt%of Cu(CH_(3)COO)_(2)by mechanical mixing and incipient wetness impregnation.Four anthracite samples of diferent fraction with d<0.1 mm,d=0.1-0.5 mm,d=0.5-1.0 mm,and d=1.0-2.0 mm were compared.According to EDX mapping,incipient wetness impregnation provides a higher dispersion of the additive and its uniform distribution in the sample.The ignition and combustion characteristics of the modifed anthracite samples were studied by thermal analysis and high-speed video recording of the processes in a combustion chamber(at heating medium temperature of 800℃).It was found that copper acetate increases anthracite reactivity,which was evidenced by decreased onset temperature of combustion(ΔT_(i))by 35-190℃and reduced ignition delay time(Δτ_(i))by 2.1-5.4 s.Copper acetate reduces fuel underburning(on average by 70%)in the ash residue of anthracite and decreases the amount of CO and NO_(x)in gas-phase products(on average by 18.5%and 20.8%,respectively).The mechanism for activation of anthracite combustion by copper acetate is proposed.展开更多
The ability to generate(di)haploid plants has provided a strategy to significantly accelerate the crop-breeding process.The major advantage of doubled haploids to breeders lies in the simultaneous genetic fixation at ...The ability to generate(di)haploid plants has provided a strategy to significantly accelerate the crop-breeding process.The major advantage of doubled haploids to breeders lies in the simultaneous genetic fixation at every locus within a single generational step.Hence,each doubled haploid(DH)represents a pure line that can be further evaluated for the range of agronomically important traits.Haploids have been induced mainly through the generation of plants from cultivated gametophytic(haploid)cells,i.e.,in vitro haploid technologies,or through the selective loss of one parental chromosome set upon inter-or intraspecific hybridization,i.e.,in vivo haploid induction.However,in many crop species,efficient haploid technology is not yet available or only applicable to a limited number of genotypes(reviewed by Jacquier et al.,2020).Due to the limits and costs of current haploid technologies,plant breeders are highly interested in any methodological improvements.An efficient DH production system with low genotype dependency based on the in vivo approach exists so far only in maize.The haploid-inducing capacity of the inbred line Stock6,originally reported to cause haploid induction rates of 2.3%–3.2%(Coe,1959),was further increased to above 8%in various inducer breeding programs(reviewed by Jacquier et al.,2020).The underlying genetics of the in vivo haploid induction process is quite complex.However,in recent years significant advances have been made in elucidating the major players.展开更多
We report results of experiments performed with the KEDR detector at the VEPP-4M e^+e^- collider. They include precise measurement of the D^0 and D^± meson masses, determination of the ψ(3770) resonance param...We report results of experiments performed with the KEDR detector at the VEPP-4M e^+e^- collider. They include precise measurement of the D^0 and D^± meson masses, determination of the ψ(3770) resonance parameters, and a search for narrow resonances in e^+e^- annihilation at center-of-mass energies between 1.85 and 3.1 GeV.展开更多
Objective:To access the in vitro antibacterial activity of Hibiscus rosa-sinensis(H.rosa-sinensis) flower extract against human pathogens.Methods:Antibacterial activity was evaluated by using disc and agar diffusion m...Objective:To access the in vitro antibacterial activity of Hibiscus rosa-sinensis(H.rosa-sinensis) flower extract against human pathogens.Methods:Antibacterial activity was evaluated by using disc and agar diffusion methods.The protein was run through poly acrylmide gel electrophoresis to view their protein profile.Results:The results showed that the cold extraction illustrates a maximum zone of inhibition against Bacillus suhtillis(B.suhtillis),Escherichia coli(E.coli) viz.,(17.00±2.91),(14.50±1.71)mm.followed by hot extraction against.E.coli.Salmonella sp.as(11.66 ±3.14),(10.60±3.09)mm.In methanol extraction showed a highest zone of inhibition recorded against B.suhtillis,E.coli as(18.86±0.18),(18.00±1.63) mm pursued by ethanol extraction shower) utmost zone of inhibition recorded against Salmonella sp.at(20.40±1.54) mm.The crude protein from flower showed a maximum inhibitory zone observed against Salmonella sp.,E.coli viz.,(16.55±1.16),(14.30±2.86)mm.The flower material can be taken as an alternative source of antibacterial agent against the human pathogens.Conclusions:The extracts of the H.rosasinensis art;proved to have potential antibacterial activity,further studies arc highly need for the drug development.展开更多
This study investigates the process of formation of ooidal ironstones in the Upper Cretaceous-Paleogene succession in western Siberia.The formation of such carbonate-based ironstones is a continuing problem in sedimen...This study investigates the process of formation of ooidal ironstones in the Upper Cretaceous-Paleogene succession in western Siberia.The formation of such carbonate-based ironstones is a continuing problem in sedimentary geology,and in this study,we use a variety of data and proxies assembled from core samples to develop a model to explain how the ooidal ironstones formed.Research on pyrite framboids and geochemical redox proxies reveals three intervals of oceanic hypoxia during the deposition of marine ooidal ironstones in the Late Cretaceous to the Early Paleogene Bakchar ironstone deposit in western Siberia;the absence of pyrite indicates oxic conditions for the remaining sequence.While goethite formed in oxic depositional condition,chamosite,pyrite and siderite represented hypoxic seawater.Euhedral pyrite crystals form through a series of transition originating from massive aggregate followed by normal and polygonal framboid.Sediments associated with goethite-chamosite ironstones,encompassing hypoxic intervals exhibit positive cerium,negative europium,and negative yttrium anomalies.Mercury anomalies,associated with the initial stages of hypoxia,correlate with global volcanic events.Redox sensitive proxies and ore mineral assemblages of deposits reflect hydrothermal activation.Rifting and global volcanism possibly induced hydrothermal convection in the sedimentary cover of western Siberia,and released iron-rich fluid and methane in coastal and shallow marine environments.This investigation,therefore,reveals a potential geological connection between Large Igneous Provinces(LIPs),marine hypoxia,rifting and the formation of ooidal ironstones in ancient West Siberian Sea.展开更多
The great deal of novel rare earth based semiconducting lanthanum barium copper oxide La3Ba3Cu6OI4 (LBC-336) were synthesized by low temperature molten salt synthesis (MSS) due to "dissolution precipitation mecha...The great deal of novel rare earth based semiconducting lanthanum barium copper oxide La3Ba3Cu6OI4 (LBC-336) were synthesized by low temperature molten salt synthesis (MSS) due to "dissolution precipitation mechanism". Here, we reported one pot synthesis of product by direct precipitation from a molten KOH-NaOH mixnare at 450 ℃ and single phase La3Ba3Cu6014 with tetragonal crystal system. The particle size of 140-200 nm were observed in both PXRD pattern and HRSEM micrographs and it showed a cubic morphology. The semiconducting nature was extracted from various parameters like optical band gap (1.8 eV), AC conductivity (0.70 eV), DC conductivity (0.70 eV), and also Hall effect parameters like the charge carrier concentration values n=6,0x 1026 m-3 and it proved as a p-type semiconductor. The electrical phase trasition temperature from ferroelectric to antiferroelec- tric system (Tin=420 K) and anti-ferroelectric - paraelectric system (depolarization temperature Ta=673 K) which attributed to the space charge polarization contributed to the conduction mechanism. The magnetic phase transitions were from ferromagnetic to ferrimagnetic system (Curie temperature (Tc=70 K)) and it led to soft magnetic material and also held good for superconductor appli- cation upto 70 K.展开更多
Sedimentary successions in the northwestern Gulf of Suez provide important clues to the understanding of the geological evolution of NE Africa during the middle and late Eocene.This study focuses on detailed facies an...Sedimentary successions in the northwestern Gulf of Suez provide important clues to the understanding of the geological evolution of NE Africa during the middle and late Eocene.This study focuses on detailed facies analyses in order to characterize the depositional environments and system tracts of the Bartonian-Priabonian succession cropping out in this area.Bartonian-Priabonian carbonate deposits in five stratigraphic sections constitute,from base to top,the Gebel Hof,Observatory,Sannur,Qurn,and Wadi Hof Formations.These formations contain four local assemblage zones of larger benthic foraminifers.Analyses of litho-,bio-,and microfacies in the succession resulted in the recognition of 12 lithofacies types.These lithofacies are represented by packages of lime-mudstones,wackestones,packstones,pack-to grainstones,grainstones,rudstones,boundstones and dolomites.These lithofacies have been grouped into four geneticallyrelated facies associations that represent,respectively,tidal flats/shallow subtidal,restricted-shelf/lagoonal,shoal bar,and outer-shelf lagoon/reefal depositional environments in a downslope shallow-marine inner-ramp setting.The vertical transitions of these facies associations,representing facies changes through time,imply fluctuations of the regional sea level.The two peaks in the Bartonian correspond to well-known global eustatic sea-level rises;the pronounced Priabonian regression must be ascribed to the known global eustatic sea-level fall in combination with regional tectonic activity.The facies distribution suggests that the study area was located in the direct vicinity of some islands during the Bartonian-Priabonian.展开更多
Introduction The climax of the industrial revolution was marked by the rapid growth of industry,and advancement in technologies have further fueled this industrial expansion,leading to a surge in economic growth.Howev...Introduction The climax of the industrial revolution was marked by the rapid growth of industry,and advancement in technologies have further fueled this industrial expansion,leading to a surge in economic growth.However.these technologies have also increased the degree of destructive human inter-ference with the biosphere.展开更多
Gastrointestinal stromal tumours (GIST) are mesenchymal tumours that arise most commonly from the stomach. They are the 3rd most common tumour diagnosed behind adenocarcinomas and lymphomas. The majority of these tumo...Gastrointestinal stromal tumours (GIST) are mesenchymal tumours that arise most commonly from the stomach. They are the 3rd most common tumour diagnosed behind adenocarcinomas and lymphomas. The majority of these tumours are asymptomatic and incidentally diagnosed in UGI scopy or contrast enhanced CT abdomen and pelvis studies. Obstruction, ulceration, gastrointestinal (GI) haemorrhage and perforation warrants an urgent surgical intervention. GIST is medically managed by tyrosine kinase inhibitors and surgically by resection and anastomosis. This case report highlights the diagnosis and management of a 42-year-old gentleman who presented with vague right iliac fossa mass. Informed consent was obtained from the patient for publication of this case. This case was chosen to be reported because of the rare incidence of small intestine GIST in South India and the effectiveness of minimally invasive laparoscopic surgery in management.展开更多
Shaft development can be documented on the basis of comparative studies of specific shaft lengths and shaft patterns.We calculated the specific length of shafts and the average specific shaft length of the shafts in s...Shaft development can be documented on the basis of comparative studies of specific shaft lengths and shaft patterns.We calculated the specific length of shafts and the average specific shaft length of the shafts in some karst areas and we investigated the relation between the altitude of shaft floors and the specific shaft length.Taking the registered specific shaft lengths and the shaft patterns into consideration,it can be stated that some parts of the shafts developed paragenetically in the studied karst areas.In the Bakony Region,this was caused by surface water influx,rise of karst water level,and their simultaneous effect.As a result,shaft systems,bifurcating shafts and storeyed shafts developed.On glaciokarst areas,shafts may constitute a system with phreatic passages:either because a phreatic environment developed in the vadose zone due to the permanent impoundment of karst water or because a phreatic passage got into the vadose zone since the karst became elevated.On the studied karst areas,the following shaft development types are distinguished:glacial-high mountain surface flood development type(1),glacial-high mountain karst water and surface flood development type(2),glacial karst water and surface flood later phreatic development type(3),shaft with a passage that got into the vadose zone(4).展开更多
This paper discusses some aspects of interdisciplinary problems of industrial automation curriculum in Virumaa College of Tallinn University of Technology at engineering level. The problems being faced by engineers ar...This paper discusses some aspects of interdisciplinary problems of industrial automation curriculum in Virumaa College of Tallinn University of Technology at engineering level. The problems being faced by engineers are increasingly interdisciplinary and complicated because the development of new products and processes depends upon the integration of many different technologies. Expansion of possibilities of already existing fieldbus systems is carried out by means of integration them into Profinet (PROcess Field NET) communications. The lab set-model of vertical integration-for data gathering from smart Profibus PA sensor, data transmission, controllers configuration for Profinet IO direct interfacing of distributed field devices on the Ethernet is discussed in this paper.展开更多
Long-term geological processes are usually described with curves reflecting continuous changes in the characteristic parameters through the geological history, and such curves can be employed directly for recognition ...Long-term geological processes are usually described with curves reflecting continuous changes in the characteristic parameters through the geological history, and such curves can be employed directly for recognition of episodic(relatively long-term) events linked to these changes. The episodic events can be classified into several categories according to their scale(ordinary and anomalous events), "shape"(positive, negative, and neutral events), and relation to long-term trend change(successive, interruptive,facilitative, stabilizing, transformative, increasing, and decreasing). Many types of these events can be defined depending on the combination of the above-mentioned patterns. Of course, spatial rank,duration, and origin can be also considered in description of these events. The proposed classification can be applied to events in some real long-term geological processes, which include global sea-level changes,biodiversity dynamics, lithospheric plate number changes, and palaeoclimate changes. Several case examples prove the usefulness of the classification. It is established that the Early Valanginian(Early Cretaceous) eustatic lowstand(the lowest position of the sea level in the entire Cretaceous) was negative,but ordinary and only interruptive event. In the other case, it becomes clear that the only end-Ordovician and the Permian/Triassic mass extinctions transformed the trends of the biodiversity dynamics(from increase to decrease and from decrease to increase respectively), and the only Cretaceous/Paleogene mass extinction was really anomalous event on the Phanerozoic biodiversity curve. The new palaeontological data are employed to reconstruct the diversity dynamics of brachiopods in Germany(without the Alps) and the Swiss Jura Mountains. The further interpretation of the both diversity curves implies that the Early Toarcian mass extinction affected the regional brachiopod faunas strongly, but this event was only decreasing(biotic radiation continued after it, although "restarted" from the lower point)s展开更多
Many gastropod taxa went extinct during the Late Cretaceous. The stratigraphic ranges of 268 genera permit to establish the longevity of extinction victims for each stage of this epoch. "Young" taxa (originated wit...Many gastropod taxa went extinct during the Late Cretaceous. The stratigraphic ranges of 268 genera permit to establish the longevity of extinction victims for each stage of this epoch. "Young" taxa (originated within B epochs before the extinction) prevailed among victims of the extinctions in all stages. The proportion of "old" taxa (originated before the Cretaceous) that went extinct was the highest in the Cenomanian, and it was the lowest in the Coniacian and the Maastrichtian. It appears that the end-Cretaceous mass extinction affected chiefly "young" taxa. However, the comparison with the earlier time intervals suggests that this pattern of selectivity by generic longevity was not specific for the noted catastrophe, but, in contrast, it was typical for the entire Late Cretaceous. The latest Cenomanian environmental perturbation (OAE2) caused a stronger extinction of"old" taxa, and thus, this biotic crisis was less selective by generic longevity. This hypothesis, however, is not proven by the statistical test.展开更多
Introduction: Neurogenic tumors include schwannomas and neurofibro-mas. They occur often in the head and neck. However, their occurrence on the vagus is uncommon. A high index of suspicion is needed to order imaging i...Introduction: Neurogenic tumors include schwannomas and neurofibro-mas. They occur often in the head and neck. However, their occurrence on the vagus is uncommon. A high index of suspicion is needed to order imaging in pelvic lesions that present atypically. Discussion: Schwannomas are hypointense on T1 and heterogeneously hyperintense on T2 on MRI. The histopathological appearance with Antoni type A and type B is typical of Schwannoma. Conclusion: Schwannomas are slow growing benign tumors that are separable from the parent nerve. Recurrence is uncommon after resection.展开更多
报道了用CMD-3在2011-2012年收集的积分亮度为22 pb-1的研究结果.在CMD-3当前的统计量下,只能被确定Ф(1020)η中间共振态.在1.59-2.0 Ge V能区的30个能量点测量了e^+e^-→Ф(1020)η.分析中,将η介子当做反冲粒子,穷尽了η衰变的所有模...报道了用CMD-3在2011-2012年收集的积分亮度为22 pb-1的研究结果.在CMD-3当前的统计量下,只能被确定Ф(1020)η中间共振态.在1.59-2.0 Ge V能区的30个能量点测量了e^+e^-→Ф(1020)η.分析中,将η介子当做反冲粒子,穷尽了η衰变的所有模式,选出的事例总数为1454±48.测量的截面近似为Ф(1680)和非共振振幅按照矢量介子主导模型的叠加,并得到了Ф(1680)介子共振参数的初步结果.展开更多
文摘The novelty of this research lies in the successful fabrication of a 3D-printed honeycomb structure filled with nanofillers for acoustic properties,utilizing an impedance tube setup in accordance with ASTM standard E 1050-12.The Creality Ender-3,a 3D printer,was used for printing the honeycomb structures,and polylactic acid(PLA)material was employed for their construction.The organic,inorganic,and polymeric compounds within the composites were identified using fourier transformation infrared(FTIR)spectroscopy.The structure and homogeneity of the samples were examined using a field emission scanning electron microscope(FESEM).To determine the sound absorption coefficient of the 3D printed honeycomb structure,numerous samples were systematically developed using central composite design(CCD)and analysed using response surface methodology(RSM).The RSM mathematical model was established to predict the optimum values of each factor and noise reduction coefficient(NRC).The optimum values for an NRC of 0.377 were found to be 1.116 wt% carbon black,1.025 wt% aluminium powder,and 3.151 mm distance between parallel edges.Overall,the results demonstrate that a 3Dprinted honeycomb structure filled with nanofillers is an excellent material that can be utilized in various fields,including defence and aviation,where lightweight and acoustic properties are of great importance.
基金Supported by the Russian Foundation for Basic Research,grants 08-02-00258,08-02-00258RF Presidential Grant for Sc. Sch. NSh-5655.2008.2
文摘We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc width and mass. Our preliminary results are: M(ηc) = 2979.4± 1.5 ± 1.9 MeV/c^2, Г(ηc) = 27.8±5.1 ±3.3 MeV, B(Jψ→ηcγ) = (2.34±0.15±0.40)%.
文摘This paper addressed the efect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method.Anthracite was impregnated with 5 wt%of Cu(CH_(3)COO)_(2)by mechanical mixing and incipient wetness impregnation.Four anthracite samples of diferent fraction with d<0.1 mm,d=0.1-0.5 mm,d=0.5-1.0 mm,and d=1.0-2.0 mm were compared.According to EDX mapping,incipient wetness impregnation provides a higher dispersion of the additive and its uniform distribution in the sample.The ignition and combustion characteristics of the modifed anthracite samples were studied by thermal analysis and high-speed video recording of the processes in a combustion chamber(at heating medium temperature of 800℃).It was found that copper acetate increases anthracite reactivity,which was evidenced by decreased onset temperature of combustion(ΔT_(i))by 35-190℃and reduced ignition delay time(Δτ_(i))by 2.1-5.4 s.Copper acetate reduces fuel underburning(on average by 70%)in the ash residue of anthracite and decreases the amount of CO and NO_(x)in gas-phase products(on average by 18.5%and 20.8%,respectively).The mechanism for activation of anthracite combustion by copper acetate is proposed.
文摘The ability to generate(di)haploid plants has provided a strategy to significantly accelerate the crop-breeding process.The major advantage of doubled haploids to breeders lies in the simultaneous genetic fixation at every locus within a single generational step.Hence,each doubled haploid(DH)represents a pure line that can be further evaluated for the range of agronomically important traits.Haploids have been induced mainly through the generation of plants from cultivated gametophytic(haploid)cells,i.e.,in vitro haploid technologies,or through the selective loss of one parental chromosome set upon inter-or intraspecific hybridization,i.e.,in vivo haploid induction.However,in many crop species,efficient haploid technology is not yet available or only applicable to a limited number of genotypes(reviewed by Jacquier et al.,2020).Due to the limits and costs of current haploid technologies,plant breeders are highly interested in any methodological improvements.An efficient DH production system with low genotype dependency based on the in vivo approach exists so far only in maize.The haploid-inducing capacity of the inbred line Stock6,originally reported to cause haploid induction rates of 2.3%–3.2%(Coe,1959),was further increased to above 8%in various inducer breeding programs(reviewed by Jacquier et al.,2020).The underlying genetics of the in vivo haploid induction process is quite complex.However,in recent years significant advances have been made in elucidating the major players.
基金Supported by Russian Foundation for Basic Research,Grant 04-02-16712,07-02-00816,07-02-01162RF Presidential Grant for Sc.Sch.NSh-5655.2008.2
文摘We report results of experiments performed with the KEDR detector at the VEPP-4M e^+e^- collider. They include precise measurement of the D^0 and D^± meson masses, determination of the ψ(3770) resonance parameters, and a search for narrow resonances in e^+e^- annihilation at center-of-mass energies between 1.85 and 3.1 GeV.
文摘Objective:To access the in vitro antibacterial activity of Hibiscus rosa-sinensis(H.rosa-sinensis) flower extract against human pathogens.Methods:Antibacterial activity was evaluated by using disc and agar diffusion methods.The protein was run through poly acrylmide gel electrophoresis to view their protein profile.Results:The results showed that the cold extraction illustrates a maximum zone of inhibition against Bacillus suhtillis(B.suhtillis),Escherichia coli(E.coli) viz.,(17.00±2.91),(14.50±1.71)mm.followed by hot extraction against.E.coli.Salmonella sp.as(11.66 ±3.14),(10.60±3.09)mm.In methanol extraction showed a highest zone of inhibition recorded against B.suhtillis,E.coli as(18.86±0.18),(18.00±1.63) mm pursued by ethanol extraction shower) utmost zone of inhibition recorded against Salmonella sp.at(20.40±1.54) mm.The crude protein from flower showed a maximum inhibitory zone observed against Salmonella sp.,E.coli viz.,(16.55±1.16),(14.30±2.86)mm.The flower material can be taken as an alternative source of antibacterial agent against the human pathogens.Conclusions:The extracts of the H.rosasinensis art;proved to have potential antibacterial activity,further studies arc highly need for the drug development.
基金Laboratory geochemical investigations were carried out at National Research Tomsk Polytechnic University within the framework of a Competitiveness Enhancement Program Grant(Project VIU-OG-61/2019)funded by Russian Foundation for Basic Research and Tomsk Region(19–45-703002).
文摘This study investigates the process of formation of ooidal ironstones in the Upper Cretaceous-Paleogene succession in western Siberia.The formation of such carbonate-based ironstones is a continuing problem in sedimentary geology,and in this study,we use a variety of data and proxies assembled from core samples to develop a model to explain how the ooidal ironstones formed.Research on pyrite framboids and geochemical redox proxies reveals three intervals of oceanic hypoxia during the deposition of marine ooidal ironstones in the Late Cretaceous to the Early Paleogene Bakchar ironstone deposit in western Siberia;the absence of pyrite indicates oxic conditions for the remaining sequence.While goethite formed in oxic depositional condition,chamosite,pyrite and siderite represented hypoxic seawater.Euhedral pyrite crystals form through a series of transition originating from massive aggregate followed by normal and polygonal framboid.Sediments associated with goethite-chamosite ironstones,encompassing hypoxic intervals exhibit positive cerium,negative europium,and negative yttrium anomalies.Mercury anomalies,associated with the initial stages of hypoxia,correlate with global volcanic events.Redox sensitive proxies and ore mineral assemblages of deposits reflect hydrothermal activation.Rifting and global volcanism possibly induced hydrothermal convection in the sedimentary cover of western Siberia,and released iron-rich fluid and methane in coastal and shallow marine environments.This investigation,therefore,reveals a potential geological connection between Large Igneous Provinces(LIPs),marine hypoxia,rifting and the formation of ooidal ironstones in ancient West Siberian Sea.
基金VIT University for providing major financial support
文摘The great deal of novel rare earth based semiconducting lanthanum barium copper oxide La3Ba3Cu6OI4 (LBC-336) were synthesized by low temperature molten salt synthesis (MSS) due to "dissolution precipitation mechanism". Here, we reported one pot synthesis of product by direct precipitation from a molten KOH-NaOH mixnare at 450 ℃ and single phase La3Ba3Cu6014 with tetragonal crystal system. The particle size of 140-200 nm were observed in both PXRD pattern and HRSEM micrographs and it showed a cubic morphology. The semiconducting nature was extracted from various parameters like optical band gap (1.8 eV), AC conductivity (0.70 eV), DC conductivity (0.70 eV), and also Hall effect parameters like the charge carrier concentration values n=6,0x 1026 m-3 and it proved as a p-type semiconductor. The electrical phase trasition temperature from ferroelectric to antiferroelec- tric system (Tin=420 K) and anti-ferroelectric - paraelectric system (depolarization temperature Ta=673 K) which attributed to the space charge polarization contributed to the conduction mechanism. The magnetic phase transitions were from ferromagnetic to ferrimagnetic system (Curie temperature (Tc=70 K)) and it led to soft magnetic material and also held good for superconductor appli- cation upto 70 K.
文摘Sedimentary successions in the northwestern Gulf of Suez provide important clues to the understanding of the geological evolution of NE Africa during the middle and late Eocene.This study focuses on detailed facies analyses in order to characterize the depositional environments and system tracts of the Bartonian-Priabonian succession cropping out in this area.Bartonian-Priabonian carbonate deposits in five stratigraphic sections constitute,from base to top,the Gebel Hof,Observatory,Sannur,Qurn,and Wadi Hof Formations.These formations contain four local assemblage zones of larger benthic foraminifers.Analyses of litho-,bio-,and microfacies in the succession resulted in the recognition of 12 lithofacies types.These lithofacies are represented by packages of lime-mudstones,wackestones,packstones,pack-to grainstones,grainstones,rudstones,boundstones and dolomites.These lithofacies have been grouped into four geneticallyrelated facies associations that represent,respectively,tidal flats/shallow subtidal,restricted-shelf/lagoonal,shoal bar,and outer-shelf lagoon/reefal depositional environments in a downslope shallow-marine inner-ramp setting.The vertical transitions of these facies associations,representing facies changes through time,imply fluctuations of the regional sea level.The two peaks in the Bartonian correspond to well-known global eustatic sea-level rises;the pronounced Priabonian regression must be ascribed to the known global eustatic sea-level fall in combination with regional tectonic activity.The facies distribution suggests that the study area was located in the direct vicinity of some islands during the Bartonian-Priabonian.
文摘Introduction The climax of the industrial revolution was marked by the rapid growth of industry,and advancement in technologies have further fueled this industrial expansion,leading to a surge in economic growth.However.these technologies have also increased the degree of destructive human inter-ference with the biosphere.
文摘Gastrointestinal stromal tumours (GIST) are mesenchymal tumours that arise most commonly from the stomach. They are the 3rd most common tumour diagnosed behind adenocarcinomas and lymphomas. The majority of these tumours are asymptomatic and incidentally diagnosed in UGI scopy or contrast enhanced CT abdomen and pelvis studies. Obstruction, ulceration, gastrointestinal (GI) haemorrhage and perforation warrants an urgent surgical intervention. GIST is medically managed by tyrosine kinase inhibitors and surgically by resection and anastomosis. This case report highlights the diagnosis and management of a 42-year-old gentleman who presented with vague right iliac fossa mass. Informed consent was obtained from the patient for publication of this case. This case was chosen to be reported because of the rare incidence of small intestine GIST in South India and the effectiveness of minimally invasive laparoscopic surgery in management.
文摘Shaft development can be documented on the basis of comparative studies of specific shaft lengths and shaft patterns.We calculated the specific length of shafts and the average specific shaft length of the shafts in some karst areas and we investigated the relation between the altitude of shaft floors and the specific shaft length.Taking the registered specific shaft lengths and the shaft patterns into consideration,it can be stated that some parts of the shafts developed paragenetically in the studied karst areas.In the Bakony Region,this was caused by surface water influx,rise of karst water level,and their simultaneous effect.As a result,shaft systems,bifurcating shafts and storeyed shafts developed.On glaciokarst areas,shafts may constitute a system with phreatic passages:either because a phreatic environment developed in the vadose zone due to the permanent impoundment of karst water or because a phreatic passage got into the vadose zone since the karst became elevated.On the studied karst areas,the following shaft development types are distinguished:glacial-high mountain surface flood development type(1),glacial-high mountain karst water and surface flood development type(2),glacial karst water and surface flood later phreatic development type(3),shaft with a passage that got into the vadose zone(4).
文摘This paper discusses some aspects of interdisciplinary problems of industrial automation curriculum in Virumaa College of Tallinn University of Technology at engineering level. The problems being faced by engineers are increasingly interdisciplinary and complicated because the development of new products and processes depends upon the integration of many different technologies. Expansion of possibilities of already existing fieldbus systems is carried out by means of integration them into Profinet (PROcess Field NET) communications. The lab set-model of vertical integration-for data gathering from smart Profibus PA sensor, data transmission, controllers configuration for Profinet IO direct interfacing of distributed field devices on the Ethernet is discussed in this paper.
基金Supported by the Russian Science Foundation(14-50-00080)Russian Foundation for Basic Research(13-02-00215-a+6 种基金13-02-01134-a14-02-00580-a14-02-31275-mol-a14-02-00047-a14-02-31478-mol-a14-02-9133215-02-05674)
文摘Long-term geological processes are usually described with curves reflecting continuous changes in the characteristic parameters through the geological history, and such curves can be employed directly for recognition of episodic(relatively long-term) events linked to these changes. The episodic events can be classified into several categories according to their scale(ordinary and anomalous events), "shape"(positive, negative, and neutral events), and relation to long-term trend change(successive, interruptive,facilitative, stabilizing, transformative, increasing, and decreasing). Many types of these events can be defined depending on the combination of the above-mentioned patterns. Of course, spatial rank,duration, and origin can be also considered in description of these events. The proposed classification can be applied to events in some real long-term geological processes, which include global sea-level changes,biodiversity dynamics, lithospheric plate number changes, and palaeoclimate changes. Several case examples prove the usefulness of the classification. It is established that the Early Valanginian(Early Cretaceous) eustatic lowstand(the lowest position of the sea level in the entire Cretaceous) was negative,but ordinary and only interruptive event. In the other case, it becomes clear that the only end-Ordovician and the Permian/Triassic mass extinctions transformed the trends of the biodiversity dynamics(from increase to decrease and from decrease to increase respectively), and the only Cretaceous/Paleogene mass extinction was really anomalous event on the Phanerozoic biodiversity curve. The new palaeontological data are employed to reconstruct the diversity dynamics of brachiopods in Germany(without the Alps) and the Swiss Jura Mountains. The further interpretation of the both diversity curves implies that the Early Toarcian mass extinction affected the regional brachiopod faunas strongly, but this event was only decreasing(biotic radiation continued after it, although "restarted" from the lower point)s
基金Supported by Russian Fundation for Basic Research(10-02-00695-a10-02-00253-a+8 种基金11-02-00328-a11-02-00112-a12-02-31501-mol-a12-02-31499-mol-a12-02-31498-mol-a12-02-01032-a13-02-00215-a15-02-05674-a)Federal Target Program(14.B37.21.07777)
文摘Many gastropod taxa went extinct during the Late Cretaceous. The stratigraphic ranges of 268 genera permit to establish the longevity of extinction victims for each stage of this epoch. "Young" taxa (originated within B epochs before the extinction) prevailed among victims of the extinctions in all stages. The proportion of "old" taxa (originated before the Cretaceous) that went extinct was the highest in the Cenomanian, and it was the lowest in the Coniacian and the Maastrichtian. It appears that the end-Cretaceous mass extinction affected chiefly "young" taxa. However, the comparison with the earlier time intervals suggests that this pattern of selectivity by generic longevity was not specific for the noted catastrophe, but, in contrast, it was typical for the entire Late Cretaceous. The latest Cenomanian environmental perturbation (OAE2) caused a stronger extinction of"old" taxa, and thus, this biotic crisis was less selective by generic longevity. This hypothesis, however, is not proven by the statistical test.
文摘Introduction: Neurogenic tumors include schwannomas and neurofibro-mas. They occur often in the head and neck. However, their occurrence on the vagus is uncommon. A high index of suspicion is needed to order imaging in pelvic lesions that present atypically. Discussion: Schwannomas are hypointense on T1 and heterogeneously hyperintense on T2 on MRI. The histopathological appearance with Antoni type A and type B is typical of Schwannoma. Conclusion: Schwannomas are slow growing benign tumors that are separable from the parent nerve. Recurrence is uncommon after resection.
基金Supported in Part by the Russian Science Foundation(14-50-00080)Russian Foundation for Basic Research(RFBR 13-02-00215-a,RFBR 13-02-01134-a,RFBR 14-02-00580-a,RFBR 14-02-31275-mol-a,RFBR 14-02-00047-a,RFBR 14-02-31478-mol-a,RFBR 14-02-91332,RFBR 15-02-0567)
文摘报道了用CMD-3在2011-2012年收集的积分亮度为22 pb-1的研究结果.在CMD-3当前的统计量下,只能被确定Ф(1020)η中间共振态.在1.59-2.0 Ge V能区的30个能量点测量了e^+e^-→Ф(1020)η.分析中,将η介子当做反冲粒子,穷尽了η衰变的所有模式,选出的事例总数为1454±48.测量的截面近似为Ф(1680)和非共振振幅按照矢量介子主导模型的叠加,并得到了Ф(1680)介子共振参数的初步结果.