We report the mineralogy and geochemistry of hydrothermal sulphide from the crater of a volcanic high near 18°36.4′S of the Central Lau Spreading Center.During 1990s,that volcanic structure was reported active a...We report the mineralogy and geochemistry of hydrothermal sulphide from the crater of a volcanic high near 18°36.4′S of the Central Lau Spreading Center.During 1990s,that volcanic structure was reported active and sulphide samples were collected by MIR submersible.A section of a chimney-like structure from the crater-floor was studied here.The Fe-depleted sphalerites,and Co-depleted pyrites in that chimney were similar to those commonly found in low to moderate temperature(<300℃)sulphides from sediment-starved hydrothermal systems.Bulk analyses of three parts of that chimney section showed substantial enrichment of Zn(18%–20%)and Fe(14%–27%)but depletion of Cu(0.8%–1.3%).In chondrite-normalized rare earth element-patterns,the significant negative Ce-anomalies(Ce/Ce*=0.27–0.39)and weakly positive Eu-anomalies(Eu/Eu*=1.60–1.68)suggested sulphide mineralisation took place from reduced low-temperature fluid.The depleted concentration of lithophiles in this sulphide indicates restricted contribution of sub-ducting plate in genesis of source fluid as compared to those from other parts of Lau Spreading Centre.Uniform mineralogy and bulk composition of subsamples across the chimney section suggests barely any alteration of fluid composition and/or mode of mineralisation occurred during its growth.展开更多
Drought is one of the critical conditions for the growth and productivity of many crops including mung bean(Vigna radiata L.Wilczek).Screening of genotypes for variations is one of the suitable strategies for evaluati...Drought is one of the critical conditions for the growth and productivity of many crops including mung bean(Vigna radiata L.Wilczek).Screening of genotypes for variations is one of the suitable strategies for evaluating crop adaptability and global food security.In this context,the study investigated the physiological and biochemical responses of four drought tolerant(BARI Mung-8,BMX-08010-2,BMX-010015,BMX-08009-7),and four drought sensitive(BARI Mung-1,BARI Mung-3,BU Mung-4,BMX-05001)mung bean genotypes under wellwatered(WW)and water deficit(WD)conditions.The WW treatment maintained sufficient soil moisture(22%±0.5%,i.e.,30%deficit of available water)by regularly supplying water.Whereas,the WD treatment was maintained throughout the growing period,and water was applied when the wilting symptom appeared.The drought tolerant(DT)genotypes BARI Mung-8,BMX-08010-2,BMX-010015,BMX-08009-7 showed a high level of proline accumulation(2.52–5.99 mg g^(−1) FW),photosynthetic pigment(total chlorophyll 2.96–3.27 mg g^(−1) FW at flowering stage,and 1.62–2.38 mg g^(−1) FW at pod developing stage),plant water relation attributes including relative water content(RWC)(82%–84%),water retention capacity(WRC)(12–14)as well as lower water saturation deficit(WSD)(19%–23%),and water uptake capacity(WUC)(2.58–2.89)under WD condition,which provided consequently higher relative seed yield.These indicate that the tolerant genotypes gained better physiobiochemical attributes and adaptability in response to drought conditions.Furthermore,the genotype BMX-08010-2 showed superiority in terms of those physio-biochemical traits,susceptibility index(SSI)and stress tolerance index(STI)to other genotypes.Based on the physiological and biochemical responses,the BMX-08010-2 was found to be a suitable genotype for sustaining yield under drought stress,and subsequently,it could be recommended for crop improvement through hybridization programs.In addition,the identified traits can be used as markers to identify tolerant genotypes for drought-prone areas.展开更多
Earthquakes and the tsunamis they produce are the world’s most devastating natural disasters, affecting more than 100 countries. Not surprisingly, the problem of earthquake prediction has occupied scientists’ minds ...Earthquakes and the tsunamis they produce are the world’s most devastating natural disasters, affecting more than 100 countries. Not surprisingly, the problem of earthquake prediction has occupied scientists’ minds for more than two thousand years. This paper provides theoretical and practical arguments regarding the possibility of predicting strong and major earthquakes worldwide. Many strong and major earthquakes can be predicted at least two to five months in advance, based on identifying stressed areas that begin to behave abnormally before strong events, with the size of these areas corres</span><span style="font-family:Verdana;">ponding to Dobrovolsky’s formula. We make predictions by combining</span><span style="font-family:Verdana;"> knowledge from many different disciplines: physics, geophysics, seismology, geology, and earth science, among others. An integrated approach is used to identify anomalies and make predictions, including satellite remote sensing techniques and data from ground-based instruments. Terabytes of information are currently processed every day with many different multi-parametric prediction systems applied thereto. Alerts are issued if anomalies are confirmed by a few different systems. It has been found that geophysical patterns of earthquake preparation and stress accumulation are similar for all key seismic regions. The same earthquake prediction methodologies and systems have been successfully applied in global practice since 2013, with the technology successfully used to retrospectively test against more than 700 strong and major earthquakes since 1970. In other words, the earthquake prediction problem has largely been solved. Throughout 2017-2021, results were presented to more than 160 professors from 63 countries.展开更多
People's working capability is badly affected when they sufer an amputated arm.Artifcial replacements with prosthetic devices to get a satisfactory level of performance for essential functions with the currently a...People's working capability is badly affected when they sufer an amputated arm.Artifcial replacements with prosthetic devices to get a satisfactory level of performance for essential functions with the currently available prosthetic technology are very dificult.Myoelectric arm prostheses are becoming popular because they are operated by a natural contraction of intact muscles.Hence,SEMG based artifdal arm was fabricated.The system cousists of diferent electronic and mechanical assemblies for operation of hand utilizing microcontroller in order to have minimum signal loss during its processing.With the hep of relay switching connected to low power DC motor,system is capable of opening and closing of grip according to individual wish.展开更多
Investigation of new orbit geometries exhibits a very attractive behavior for a spacecraft to monitor space weather coming from the Sun. Several orbit transfer mechanisms are analyzed as potential alternatives to moni...Investigation of new orbit geometries exhibits a very attractive behavior for a spacecraft to monitor space weather coming from the Sun. Several orbit transfer mechanisms are analyzed as potential alternatives to monitor solar activity such as a sub-solar orbit or quasi-satellite orbit and short and long heteroclinic and homoclinic connections between the triangular points L4 and L5 and the collinear point L3 of the CRTBP （circular restricted three-body problem） in the Sun-Earth system. These trajectories could serve as channels through where material can be transported from L5 to L3 by performing small maneuvers at the departure of the Trojan orbit. The size of these maneuvers at L5 is between 299 m/s and 730 m/s depending on the transfer time of the trajectory and does not need any deterministic maneuvers at L3. Our results suggest that material may also be transported from the Trojan orbits to quasi-satellite orbits or even displaced quasi-satellite orbits.展开更多
Beryl-Al6061 alloy composites having 2-12 wt% of beryl particles were fabricated by liquid metallurgy (stir cast) method. The tensile and wear properties of beryl-Al6061 composites have been evaluated and compared wit...Beryl-Al6061 alloy composites having 2-12 wt% of beryl particles were fabricated by liquid metallurgy (stir cast) method. The tensile and wear properties of beryl-Al6061 composites have been evaluated and compared with its base alloy. The results revealed that the Al6061-10 wt% of beryl composites shows an improvement of 15.38% in tensile strength and specific wear rate decreases by 8.9% at normal load of 9.81N when compared to matrix i.e. base alloy. Significant improvement in tensile properties and hardness are noticed as the wt% of the beryl particles increases. The microstructures of the composites were studied to know the uniform dispersion of the beryl particles in matrix. It has been observed that addition of beryl particles significantly improves ultimate tensile strength and hardness properties as compared with that of unreinforced matrix.展开更多
This paper presents the work conducted on the chemical constituents of some common and widely distributed halophyte taxa from Cyprus with the aim that these studies will help in the evaluation of halophytes for differ...This paper presents the work conducted on the chemical constituents of some common and widely distributed halophyte taxa from Cyprus with the aim that these studies will help in the evaluation of halophytes for different economical purposes.The plant species of Crithmum maritimum L.,Limbarda crithmoides(L.)Dumort,Atriplex portulacoides L.,Salsola kali L.,Atriplex halimus L.,Limonium oleifolium Mill.,L.meyeri(Boiss.)Kuntze;and Tetraena alba(L.f.)Beier&Thulin were collected in the middle of July.The shoot tissue and leaf samples were collected from the natural habitats and left for drying under air circulation followed by placing them in oven at 60°C for 96 hours.The material was crushed using mortar and pestle and subjected to an analysis of macro-and micro-nutrients and biochemical compounds.K+/Na+in the leaf tissues of the dicot species showed relatively high values depicting their behavior as Na+includes but very low Cl-levels were recorded.Out of the species investigated here in 4 TFAA content was rather high.Values ranging from 0.5%to 1%dry weight were exhibited in one species.However,only 3 species showed very low TFAA values.Later may be due to low nitrogen availability in their environment.The phenetic analyses of eight halophyte species performed on the data matrix using Ntsys-pc program version 2.1 revealed that,cluster analysis of the overall results obtained here leads to 2 clusters.This discrimination appears to be as a result of their different abilities to accumulate either proline or glycine betaine.展开更多
文摘We report the mineralogy and geochemistry of hydrothermal sulphide from the crater of a volcanic high near 18°36.4′S of the Central Lau Spreading Center.During 1990s,that volcanic structure was reported active and sulphide samples were collected by MIR submersible.A section of a chimney-like structure from the crater-floor was studied here.The Fe-depleted sphalerites,and Co-depleted pyrites in that chimney were similar to those commonly found in low to moderate temperature(<300℃)sulphides from sediment-starved hydrothermal systems.Bulk analyses of three parts of that chimney section showed substantial enrichment of Zn(18%–20%)and Fe(14%–27%)but depletion of Cu(0.8%–1.3%).In chondrite-normalized rare earth element-patterns,the significant negative Ce-anomalies(Ce/Ce*=0.27–0.39)and weakly positive Eu-anomalies(Eu/Eu*=1.60–1.68)suggested sulphide mineralisation took place from reduced low-temperature fluid.The depleted concentration of lithophiles in this sulphide indicates restricted contribution of sub-ducting plate in genesis of source fluid as compared to those from other parts of Lau Spreading Centre.Uniform mineralogy and bulk composition of subsamples across the chimney section suggests barely any alteration of fluid composition and/or mode of mineralisation occurred during its growth.
基金The authors extend their appreciation to the researchers Supporting Project No.(RSP-2021/298),King Saud University,Riyadh,Saudi Arabia.
文摘Drought is one of the critical conditions for the growth and productivity of many crops including mung bean(Vigna radiata L.Wilczek).Screening of genotypes for variations is one of the suitable strategies for evaluating crop adaptability and global food security.In this context,the study investigated the physiological and biochemical responses of four drought tolerant(BARI Mung-8,BMX-08010-2,BMX-010015,BMX-08009-7),and four drought sensitive(BARI Mung-1,BARI Mung-3,BU Mung-4,BMX-05001)mung bean genotypes under wellwatered(WW)and water deficit(WD)conditions.The WW treatment maintained sufficient soil moisture(22%±0.5%,i.e.,30%deficit of available water)by regularly supplying water.Whereas,the WD treatment was maintained throughout the growing period,and water was applied when the wilting symptom appeared.The drought tolerant(DT)genotypes BARI Mung-8,BMX-08010-2,BMX-010015,BMX-08009-7 showed a high level of proline accumulation(2.52–5.99 mg g^(−1) FW),photosynthetic pigment(total chlorophyll 2.96–3.27 mg g^(−1) FW at flowering stage,and 1.62–2.38 mg g^(−1) FW at pod developing stage),plant water relation attributes including relative water content(RWC)(82%–84%),water retention capacity(WRC)(12–14)as well as lower water saturation deficit(WSD)(19%–23%),and water uptake capacity(WUC)(2.58–2.89)under WD condition,which provided consequently higher relative seed yield.These indicate that the tolerant genotypes gained better physiobiochemical attributes and adaptability in response to drought conditions.Furthermore,the genotype BMX-08010-2 showed superiority in terms of those physio-biochemical traits,susceptibility index(SSI)and stress tolerance index(STI)to other genotypes.Based on the physiological and biochemical responses,the BMX-08010-2 was found to be a suitable genotype for sustaining yield under drought stress,and subsequently,it could be recommended for crop improvement through hybridization programs.In addition,the identified traits can be used as markers to identify tolerant genotypes for drought-prone areas.
文摘Earthquakes and the tsunamis they produce are the world’s most devastating natural disasters, affecting more than 100 countries. Not surprisingly, the problem of earthquake prediction has occupied scientists’ minds for more than two thousand years. This paper provides theoretical and practical arguments regarding the possibility of predicting strong and major earthquakes worldwide. Many strong and major earthquakes can be predicted at least two to five months in advance, based on identifying stressed areas that begin to behave abnormally before strong events, with the size of these areas corres</span><span style="font-family:Verdana;">ponding to Dobrovolsky’s formula. We make predictions by combining</span><span style="font-family:Verdana;"> knowledge from many different disciplines: physics, geophysics, seismology, geology, and earth science, among others. An integrated approach is used to identify anomalies and make predictions, including satellite remote sensing techniques and data from ground-based instruments. Terabytes of information are currently processed every day with many different multi-parametric prediction systems applied thereto. Alerts are issued if anomalies are confirmed by a few different systems. It has been found that geophysical patterns of earthquake preparation and stress accumulation are similar for all key seismic regions. The same earthquake prediction methodologies and systems have been successfully applied in global practice since 2013, with the technology successfully used to retrospectively test against more than 700 strong and major earthquakes since 1970. In other words, the earthquake prediction problem has largely been solved. Throughout 2017-2021, results were presented to more than 160 professors from 63 countries.
文摘People's working capability is badly affected when they sufer an amputated arm.Artifcial replacements with prosthetic devices to get a satisfactory level of performance for essential functions with the currently available prosthetic technology are very dificult.Myoelectric arm prostheses are becoming popular because they are operated by a natural contraction of intact muscles.Hence,SEMG based artifdal arm was fabricated.The system cousists of diferent electronic and mechanical assemblies for operation of hand utilizing microcontroller in order to have minimum signal loss during its processing.With the hep of relay switching connected to low power DC motor,system is capable of opening and closing of grip according to individual wish.
文摘Investigation of new orbit geometries exhibits a very attractive behavior for a spacecraft to monitor space weather coming from the Sun. Several orbit transfer mechanisms are analyzed as potential alternatives to monitor solar activity such as a sub-solar orbit or quasi-satellite orbit and short and long heteroclinic and homoclinic connections between the triangular points L4 and L5 and the collinear point L3 of the CRTBP （circular restricted three-body problem） in the Sun-Earth system. These trajectories could serve as channels through where material can be transported from L5 to L3 by performing small maneuvers at the departure of the Trojan orbit. The size of these maneuvers at L5 is between 299 m/s and 730 m/s depending on the transfer time of the trajectory and does not need any deterministic maneuvers at L3. Our results suggest that material may also be transported from the Trojan orbits to quasi-satellite orbits or even displaced quasi-satellite orbits.
文摘Beryl-Al6061 alloy composites having 2-12 wt% of beryl particles were fabricated by liquid metallurgy (stir cast) method. The tensile and wear properties of beryl-Al6061 composites have been evaluated and compared with its base alloy. The results revealed that the Al6061-10 wt% of beryl composites shows an improvement of 15.38% in tensile strength and specific wear rate decreases by 8.9% at normal load of 9.81N when compared to matrix i.e. base alloy. Significant improvement in tensile properties and hardness are noticed as the wt% of the beryl particles increases. The microstructures of the composites were studied to know the uniform dispersion of the beryl particles in matrix. It has been observed that addition of beryl particles significantly improves ultimate tensile strength and hardness properties as compared with that of unreinforced matrix.
文摘This paper presents the work conducted on the chemical constituents of some common and widely distributed halophyte taxa from Cyprus with the aim that these studies will help in the evaluation of halophytes for different economical purposes.The plant species of Crithmum maritimum L.,Limbarda crithmoides(L.)Dumort,Atriplex portulacoides L.,Salsola kali L.,Atriplex halimus L.,Limonium oleifolium Mill.,L.meyeri(Boiss.)Kuntze;and Tetraena alba(L.f.)Beier&Thulin were collected in the middle of July.The shoot tissue and leaf samples were collected from the natural habitats and left for drying under air circulation followed by placing them in oven at 60°C for 96 hours.The material was crushed using mortar and pestle and subjected to an analysis of macro-and micro-nutrients and biochemical compounds.K+/Na+in the leaf tissues of the dicot species showed relatively high values depicting their behavior as Na+includes but very low Cl-levels were recorded.Out of the species investigated here in 4 TFAA content was rather high.Values ranging from 0.5%to 1%dry weight were exhibited in one species.However,only 3 species showed very low TFAA values.Later may be due to low nitrogen availability in their environment.The phenetic analyses of eight halophyte species performed on the data matrix using Ntsys-pc program version 2.1 revealed that,cluster analysis of the overall results obtained here leads to 2 clusters.This discrimination appears to be as a result of their different abilities to accumulate either proline or glycine betaine.
