30 research outputs found

    Analisis Penentuan Kualitas Air Dan Status Mutu Sungai Progo Hulu Kabupaten Temanggung

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    Progo Hulu River is the main river in Progo watershed, Temanggung Regency. It was estimated that human activities have some important contributions in its water quality degradation, for example housings/settlement, agricultural, industry, etc. This research was aimed to analize Progo Hulu River which focused on (1) river water quality, (2) some factors that cause the different effects of each segment concentration, and (3) water quality status for every segment. The river water quality was observed in 12 sampling-points and then it compared with water quality standart according to the Government Act No. 82/2001. This research also describes water quality status used STORET and Pollution Index method based on Ministry Decree No. 115/2003. As result, Fecal Coliform become a dominant parameter that caused pollution in first class water quality, whereas Ammonia and Fecal Coliform caused pollution in second, third, and fourth class water quality with a main pollution source from domestic and ranch wastes. Besides, water quality status showed it has been modaretely polluted in first class water quality status and lightly- modaretely polluted in second, third, and fourth class water quality status

    HIR-CP-ABE: Hierarchical Identity Revocable Ciphertext-Policy Attribute-Based Encryption for Secure and Flexible Data Sharing

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    Ciphertext Policy Attribute-Based Encryption (CP- ABE) has been proposed to implement the attribute-based access control model. In CP-ABE, data owners encrypt the data with a certain access policy such that only data users whose attributes satisfy the access policy could obtain the corresponding private decryption key from a trusted authority. Therefore, CP-ABE is considered as a promising fine-grained access control mechanism for data sharing where no centralized trusted third party exists, for example, cloud computing, mobile ad hoc networks (MANET), Peer-to-Peer (P2P) networks, information centric networks (ICN), etc.. As promising as it is, user revocation is a cumbersome problem in CP-ABE, thus impeding its application in practice. To solve this problem, we propose a new scheme named HIR-CP-ABE, which implements hierarchical identity- based user revocation from the perceptive of encryption. In particular, the revocation is implemented by data owners directly without any help from any third party. Compared with previous attribute-based revocation solutions, our scheme provides the following nice properties. First, the trusted authority could be offline after system setup and key distribution, thus making it applicable in mobile ad hoc networks, P2P networks, etc., where the nodes in the network are unable to connect to the trusted authority after system deployment. Second, a user does not need to update the private key when user revocation occurs. Therefore, key management overhead is much lower in HIR-CP-ABE for both the users and the trusted authority. Third, the revocation mechanism enables to revoke a group of users affiliated with the same organization in a batch without influencing any other users. To the best of our knowledge, HIR-CP-ABE is the first CP-ABE scheme to provide affiliation-based revocation functionality for data owners. Through security analysis and performance evaluation, we show that the proposed scheme is secure and efficient in terms of computation, communication and storage

    Comparative mitochondrial proteomic, physiological, biochemical and ultrastructural profiling reveal factorsunderpinning salt tolerance in tetraploid black locust (Robinia pseudoacacia L.)

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    Background: Polyploidy is an important phenomenon in plants because of its roles in agricultural and forestry production as well as in plant tolerance to environmental stresses. Tetraploid black locust (Robinia pseudoacacia L.) is a polyploid plant and a pioneer tree species due to its wide ranging adaptability to adverse environments. To evaluate the ploidy-dependent differences in leaf mitochondria between diploid and tetraploid black locust under salinity stress, we conducted comparative proteomic, physiological, biochemical and ultrastructural profiling of mitochondria from leaves. Results: Mitochondrial proteomic analysis was performed with 2-DE and MALDI-TOF-MS, and the ultrastructure of leaf mitochondria was observed by transmission electron microscopy. According to 2-DE analysis, 66 proteins that responded to salinity stress significantly were identified from diploid and/or tetraploid plants and classified into 9 functional categories. Assays of physiological characters indicated that tetraploids were more tolerant to salinity stress than diploids. The mitochondrial ultrastructure of diploids was damaged more severely under salinity stress than that of tetraploids. Conclusions: Tetraploid black locust possessed more tolerance of, and ability to acclimate to, salinity stress than diploids, which may be attributable to the ability to maintain mitochondrial structure and to trigger different expression patterns of mitochondrial proteins during salinity stress.This study was supported by the Fundamental Research Funds for the Central Universities (No. 2572016EAJ4; 2572015DA03; 2572017AA23), the National Natural Science Foundation of China (31170568)

    Cell Wall Invertase 3 Affects Cassava Productivity via Regulating Sugar Allocation From Source to Sink

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    Storage roots are the main sink for photo-assimilate accumulation and reflect cassava yield and productivity. Regulation of sugar partitioning from leaves to storage roots has not been elucidated. Cell wall invertases are involved in the hydrolysis of sugar during phloem unloading of vascular plants to control plant development and sink strength but have rarely been studied in root crops like cassava. MeCWINV3 encodes a typical cell wall invertase in cassava and is mainly expressed in vascular bundles. The gene is highly expressed in leaves, especially mature leaves, in response to diurnal rhythm. When MeCWINV3 was overexpressed in cassava, sugar export from leaves to storage roots was largely inhibited and sucrose hydrolysis in leaves was accelerated, leading to increased transient starch accumulation by blocking starch degradation and reduced overall plant growth. The progress of leaf senescence was promoted in the MeCWINV3 over-expressed cassava plants with increased expression of senescence-related genes. Storage root development was also delayed because of dramatically reduced sugar allocation from leaves. As a result, the transcriptional expression of starch biosynthetic genes such as small subunit ADP-glucose pyrophosphorylase, granule-bound starch synthase I, and starch branching enzyme I was reduced in accordance with insufficient sugar supply in the storage roots of the transgenic plants. These results show that MeCWINV3 regulates sugar allocation from source to sink and maintains sugar balance in cassava, thus affecting yield of cassava storage roots

    ID-HABE: Incorporating ID-based Revocation, Delegation, and Authority Hierarchy into Attribute-Based Encryption

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    Ciphertext-Policy Attribute-Based Encryption (CP-ABE) has been proposed to implement fine-grained access control. Data owners encrypt data with a certain access policy so that only data users whose attributes satisfy the access policy can decrypt the ciphertext. A user can be automatically assigned an access privilege based on whether his/her attributes satisfying a given access policy described by attributes and their logical relations. In order to provide more flexible policy-based access control, attribute-based revocation approaches had been proposed to provide the NOT logic on attributes to allow attribute-based revocation. However, previous solutions increase the attribute management overhead when considering each user’s ID as an attribute for more precise revocations at the individual user-level. To address this issue, in this paper, an ID-ABE scheme is presented, where a user’s ID is incorporated into the key generation procedure allowing user-ID-based revocation. In addition to ID-based revocation, ID-ABE also presents a hierarchical identity structure to build a delegation framework to enable group-based revocation. In the end, we also evaluate the performance of the proposed scheme in terms of computation, storage and communication overhead, which shows the practical value of the solution for secure data sharing applications

    The complete chloroplast genome sequence of Ventilago leiocarpa Benth

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    Ventilago leiocarpa Benth. is an important medicinal and edible plant. The complete chloroplast genome of V. leiocarpa Benth. was assembled and annotated. In this study, the chloroplast genome of V. leiocarpa Benth. was a circular form of 161,880 bp in length. The genome presented a typical quadripartite structure consisting of a pair of inverted repeats (IRa and IRb) of 26,357 bp separated by a large single copy (LSC) region of 90,056 bp and a small single copy (SSC) region of 19,129 bp. The genome contained a set of 127 genes, including 82 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Phylogenetic analysis showed that V. leiocarpa Benth. closely related to Rhamnus taquetii, which beyond to Rhamnaceae

    The Effect of Rhenium Content on Microstructural Changes and Irradiated Hardening in W-Re Alloy under High-Dose Ion Irradiation

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    An amount of 100 dpa Si2+ irradiation was used to study the effect of transmutation rhenium content on irradiated microscopic defects and hardening in W-xRe (x = 0, 1, 3, 5 and 10 wt.%) alloys at 550 °C. The increase in Re content could significantly refine the grain in the W-xRe alloys, and no obvious surface topography change could be found after high-dose irradiation via the scanning electron microscope (SEM). The micro defects induced by high-dose irradiation in W and W-3Re alloys were observed using a transmission electron microscope (TEM). Dislocation loops with a size larger than 10 nm could be found in both W and W-3Re alloy, but the distribution of them was different. The distribution of the dislocation loops was more uniform in pure W, while they seemed to be clustered around some locations in W-3Re alloy. Voids (~2.4 nm) were observed in W-3Re alloy, while no void was investigated in W. High-dose irradiation induced obvious hardening with the hardening rate between 75% and 155% in all W-xRe alloys, but W-3Re alloy had the lowest hardening rate (75%). The main reasons might be related to the smallest grain size in W-3Re alloy, which suppressed the formation of defect clusters and induced smaller hardening than that in other samples

    The Effect of Rhenium Content on Microstructural Changes and Irradiated Hardening in W-Re Alloy under High-Dose Ion Irradiation

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    An amount of 100 dpa Si2+ irradiation was used to study the effect of transmutation rhenium content on irradiated microscopic defects and hardening in W-xRe (x = 0, 1, 3, 5 and 10 wt.%) alloys at 550 °C. The increase in Re content could significantly refine the grain in the W-xRe alloys, and no obvious surface topography change could be found after high-dose irradiation via the scanning electron microscope (SEM). The micro defects induced by high-dose irradiation in W and W-3Re alloys were observed using a transmission electron microscope (TEM). Dislocation loops with a size larger than 10 nm could be found in both W and W-3Re alloy, but the distribution of them was different. The distribution of the dislocation loops was more uniform in pure W, while they seemed to be clustered around some locations in W-3Re alloy. Voids (~2.4 nm) were observed in W-3Re alloy, while no void was investigated in W. High-dose irradiation induced obvious hardening with the hardening rate between 75% and 155% in all W-xRe alloys, but W-3Re alloy had the lowest hardening rate (75%). The main reasons might be related to the smallest grain size in W-3Re alloy, which suppressed the formation of defect clusters and induced smaller hardening than that in other samples

    Determination of Iridium and Rhodium in Copper Anode Slime by Inductively Coupled Plasma-Mass Spectrometry with Nickel Sulphide Fire Assay

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    BACKGROUND With the wide application of iridium and rhodium in aerospace, electronics, energy and other fields, it has become a very attractive metal in the world. In China, iridium and rhodium ore resources are relatively scarce with low grade, so it is essential to recover iridium and rhodium from secondary mineral resources. Copper anode slime enriches most of the precious metals such as iridium and rhodium in ores, which has high comprehensive recovery value. At present, there is no detection standard for iridium and rhodium in copper anode slime. The migration behavior of iridium and rhodium was not clear, so it was difficult to achieve directional enrichment and efficient extraction of iridium and rhodium metals. Therefore, the development of detection methods for iridium and rhodium in copper anode slime is an important prerequisite for the recovery and extraction of iridium and rhodium. OBJECTIVES An analytical method for accurate determination of iridium and rhodium in copper anode slime was established to maximize the utilization of mineral resources and the recycling rate of iridium, rhodium and other precious metals. At the same time, it could provide data support for the purification of iridium and rhodium in copper anode slime. METHODS In this paper, a method for determination of iridium and rhodium in copper anode slime by inductively coupled plasma-mass spectrometry (ICP-MS) with nickel sulphide fire assay was established. In the experiment, the precious metals iridium and rhodium in the sample were captured by nickel sulphide fire assay. The NiS beads were dissolved with 50% hydrochloric acid so that the precipitation of rhodium and iridium was separated from silver and other impurity elements through filtration when it was hot. The precipitates containing iridium and rhodium were effectively separated from silver and other impurity elements. The precipitate of iridium and rhodium with filter film were transferred into a closed digestion tank and dissolved in 50% aqua regia. The contents of iridium and rhodium in the solution were directly determined by ICP-MS. RESULTS The conditions such as the ingredient of nickel sulphide fire assay, the concentration of hydrochloric acid, tellurium coprecipitation, the sealing digestion time and temperature were studied. The experimental results showed that the molten slag was acidic when the ratio of nickel to sulfur was 4∶1, and it could effectively capture the iridium and rhodium in the sample with good fluidity of molten slag and the separation effect of slag buckle. When the NiS beads were dissolved by 50% hydrochloric acid, the dissolution reaction of NiS beads was suitable and complete. The precipitation containing rhodium and iridium was separated from impurity elements and filtered when hot. The precipitation was sealed and digested by dilute aqua regia (1∶1) at 160℃ for 2-3h. The possible MS interference was eliminated by selecting a suitable determination isotope. The 185Re was selected as the internal standard of 103Rh and 203Tl as the internal standard of 193Ir to eliminate the effect of signal drift, the results of iridium and rhodium had high precision and accuracy. The standard solution series of iridium and rhodium were determined under the optimized experimental conditions. The results indicated that the mass concentration of iridium and rhodium in the range of 10-100μg/L were linear to the ratio of the intensity of iridium and rhodium to the internal standard mass spectrometry. The calibration curves of iridium and rhodium were y=36674.6x+8264.7 and y=45686.7x+288.6, respectively, and the linear correlation coefficient (r) of calibration curves of iridium and rhodium were more than 0.999. The detection limits for iridium and rhodium were 0.007μg/L and 0.011μg/L, respectively, and the lower limits of detection were 0.024μg/L and 0.038μg/L, respectively. The content results of rhodium and iridium in 8 actual samples with the method showed that, the relative standard deviation (RSD, n=7) was between 1.40% and 4.57%, and the recovery was in the range of 95.00% to 103.65%. CONCLUSIONS The method has high efficiency and accuracy and can meet the detection requirements of copper anode slime samples

    The Effect of Yttrium Addition on the Microstructure and Irradiation Hardening in V-4Cr-4Ti Alloy under Self-Ion Irradiation

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    Microstructure and irradiation hardening of V-4Cr-4Ti alloys with different yttrium (Y) contents were studied by self-ion irradiation at 550 °C via TEM and nano-indentation test technology. The peak damage of the V-4Cr-4Ti-xY alloy (x = 0, 0.1, 0.5, and 1, wt.%) irradiated by 2.5 MeV self-ion (V2+) is 8 dpa. Dense dislocation loops were observed in all vanadium alloy samples after irradiation. With the increase of Y content, both average size and number density of dislocation loops using g = <110> near the pole [001] decreased, while the irradiation hardness increment first decreased and then increased. In order to better reduce the irradiation hardening, it is considered that the addition of 0.1 wt.% Y in V-4Cr-4Ti alloy is reasonable
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