[en] SA-508 Gr.3 heavy forgings were used widely for the nuclear island equipment of Nuclear Power Plant. Due to the large-scale, integration, thick wall, high performance trend, the heat treatment of SA-508 Gr.3 heavy forgings becomes more and more difficult. In the process of SA-508 Gr.3 heavy forgings localization, domestic forging factory met a lot of difficulties in heat treatment. This paper try to analyze technical characteristics of the heat treatment of SA-508 Gr.3 heavy forging for new nuclear island equipment, summary experience in the localization, and puts forward forward t technical solutions finally. (authors)

[en] As the development of nuclear technique, nuclear power heavy forgings are developing in large-scale and complexity. All these facts are imposing tremendous challenges on the smelting, forging and heat treatment capability of manufacturing enterprises. This paper introduced the development and present state of nuclear power heavy forgings manufacturing technology. The influence brought by the trend of integration of heavy forgings is analyzed. (authors)

[en] Technology characteristic of down spring forging of the second-generation, improved second-generation and the third-generation (AP1000) nuclear power technology are introduced in this paper. Summarize the experience of manufacturing of hold down spring forging of domestic enterprise. F6NM forgings have best mechanical property among all hold down spring forgings which manufactured by domestic enterprise. Therefore, F6NM forging has good prospects for development. (authors)

[en] This Paper introduced the development of Reactor Vessel Internal (RVI) heavy forgings for 1000 MW Pressurized Water Reactor (PWR) nuclear power plant, analyzed the manufacture difficulties and technical countermeasures. The testing result of the product indicated that the performance of RVI heavy forgings manufactured by Shanghai Heavy Machinery Plant Ld. (SHMP) is outstanding and entirely satisfy the technical requirements for RVI product. (authors)

[en] In order to apply the noise analysis method to measure moderator temperature coefficient of reactivity (MTC) to the reactors of power plants, the uranium solution temperature coefficient of reactivity αT for the uranium solution critical assembly was measured by using the noise analysis method in this paper, and the result was compared with the αT from the period method. The results show that the trend of the results from two measurement methods is similar. Because the αT of the uranium solution critical assembly is similar as the MTC of nuclear power plant in the influence of the reactivity change mechanism, using the noise analysis method to measure the αT of the uranium solution critical assembly has some meaningful experience for nuclear power plant to measure MTC. (authors)

[en] Highlights: • Sulfide activates sqr transcription against respiratory toxicity in Urechis unicinctus. • Sulfide increases expressions and activities of NF1, Sp1 and HSF1 in a time-dependent manner. • NF1 and Sp1 participate in both basal and early sulfide-induced sqr transcription. • HSF1 functions more significantly than NF1 and Sp1 in sulfide-induced sqr transcription. • Transcription factors NF1, Sp1 and HSF1 enhance sqr promoter activity synergistically. - Abstract: Background: Sulfide is a well-known environmental toxic substance. Mitochondrial sulfide oxidation is a main mechanism of sulfide detoxification in organisms, and sulfide: quinone oxidoreductase (SQR) is a key enzyme which is involved in transferring electrons from sulfide to ubiquinone and converting sulfide into thiosulfate. Previous studies have revealed the SQR-mediated mitochondrial sulfide oxidation exists in the echiuran worm Urechis unicinctus, and its sqr mRNA level increased significantly when the worm is exposed to sulfide. In this study, we attempt to reveal the synergistic regulation of transcription factors on sulfide-induced sqr transcription in U. unicinctus. Methods: ChIP and EMSA were used to identify the interactions between sqr proximal promoter (from −391 to +194 bp) and transcription factors NF1 (nuclear factor 1) and Sp1 (specificity protein 1). Site-directed mutation and transfection assays further revealed their binding sites and synergistic roles of HSF1, NF1 and Sp1 in the sqr transcription. When U. unicinctus were exposed to 150 μM sulfide, the expression levels and nuclear contents of NF1 and Sp1 were examined by Western blotting, and the binding contents between NF1 or Sp1 and the sqr promoter were also detected by ChIP. Results: Transcription factors NF1 and Sp1 were confirmed to interact with the sqr proximal promoter, and their binding sites were identified in −75 to −69 bp for NF1 and −210 to −201 bp for Sp1. Transfection assays showed mutation of NF1 or Sp1 binding site significantly decreased the sqr promoter activity by 50% or 73%, respectively. Moreover, we demonstrated three transcription factors NF1, Sp1 and HSF1 enhanced synergistically the activity of sqr transcription. Furthermore, contents of NF1 or Sp1 binding to the sqr proximal region increased significantly in the hindgut when the worms were exposed to 150 μM sulfide. Similar changes of NF1 or Sp1 levels and nuclear NF1 or Sp1 levels were also presented. Conclusion: Transcription factors NF1, Sp1 and HSF1 are all involved in sulfide-induced sqr transcription. Sulfide can activate sqr transcription by not only increasing their expression levels, but also promoting them entering nucleus and binding to the sqr promoter. NF1 and Sp1 participate in both basal and sulfide-induced sqr transcription, while HSF1 functions mainly in sulfide-induced sqr transcription.

[en] Based on the Lab-view operation, designing the system which can detect the position of the neutron source on the Venus II. Setting 3 proximity switches in the neutron source tube to judge if the neutron source passed the position of transducer by the procedure, and the message is fed back to operator. The test result shows that the source detection system meets the design requirement. (authors)

[en] The method principle and system composition of measuring the sub-criticality of Venus II reactor by using the source-jerk method are briefly introduced. Based on the LabVIEW platform, the source-jerk experiments under two different sub-criticalities were performed and the data were analyzed and processed. The k_eff obtained by the experiment were compared with calculated results, and they are in agreement well. (authors)

[en] A one-pot hydrothermal method was developed for the synthesis of graphene oxide quantum dots (GOQDs). It is making use of toner waste as the precursor and H₂O₂ as the oxidant. Synthesis takes 4 h and does not require strong acids or complex purification steps and does not produce environmentally harmful metal ions. The GOQDs display blue fluorescence with excitation/emission maxima at 340/445 nm. The feasibility of detecting specific DNA sequence was promoted using polyethyleneimine to modify the GOQDs surface. A method was developed to recognized a specific DNA sequence. This is based on electrostatic aggregation of GOQDs and ssDNA labeled with Dabcyl at the 3′ end, which promotes fluorescence quenching of GOQDs. The possible fluorescence quenching mechanism (which is mainly dynamic) was investigated using the Stern-Volmer equation. When a target sequence was added, which is complementary to the ssDNA, the dabcyl-labeled ssDNA is released due to strict complementary base pairing. This promotes fluorescence recovery of GOQDs. The assay has a 0.17 nM detection limit and a linear range of 0.5–30 nM. The method was used to quantify specific DNA sequences from extracts of genetically modified plant tissues.

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[en] The production structure of a manufacturing system not only influences its transportation and operation cost, but also affects logistics and parts/machine assignment decisions. Based on the sending and feedback mechanisms of information, the principles of conditional entropy and classical probability are utilized to establish structure entropy models and ordered indices of the system with dynamic characteristics and generality, which provide effective solutions for the absence of quantitative method in evaluating the structural optimization of production system. In an empirical study, this paper analyzes different production structures when workpieces are processed by different working routes before and after the implementation of cellular manufacturing. Afterwards, the developed structure entropy models and ordered indices are utilized to calculate the orderliness of production structure under the two different states. The final result verifies well the validity of this quantitative method for evaluating the orderliness of production structures.