银河智能工具机系统

银河智能工具机（ＹＨ－ＩＴＭ）是一个同时支持高速逻辑推理和数值计算，支持多种人工智能语言的通用型人工智能计算机系统，本文简要介绍了该机的硬件、软件等方面的特点。     

海藻酸钠寡糖生物活性的研究进展

海藻酸钠是细菌细胞壁及海带等褐藻类植物细胞壁的主要组成成分,因其具有很好的生物相容性、成膜性等特点,在食品医药等方面被广泛应用。其降解产物为海藻酸钠寡糖,与海藻酸钠相比具有分子量低、水溶性强、易吸收等优点,表现出多种生物活性而引起关注。综述了海藻酸钠寡糖的生物活性和应用领域研究进展,并对其发展前景进行了展望。     

王龙庄断块精细化三维地质建模

随着油田投入生产,许多油田基本上已进入中后期阶段,特点是高含水率、高采出率,开发难度变大,但大量剩余油依然存在于地下,并且分布更加零碎和繁琐,现在油田勘探的主要目的便是为了精确地呈现出剩余油的分布,进而提高采收率。为了实现这个目标,需要开展精细油藏描述,为勘探开发决策提供有力支持。根据王龙庄断块已有的井位、井斜、测井、录井等资料,以储层综合评价为基础,建立了王龙庄断块的三维地质模型,运用了比传统方法更先进的细分层方法进行建模,形成了精细油藏描述的三维可视化,最后对模型中5个主要的含油小层进行储量计算,再与原始测量得到的储量对比。王龙庄断块原始储量为116×10⁴ t,拟合储量为121.11×10⁴ t,拟合相对误差4.2%。计算结果表明,王龙庄断块储量拟合误差在允许范围之内。     

用于监测食品新鲜度的时间-温度指示器研究现状

随着人们对食品新鲜度的要求越来越高,时间-温度指示器(time-temperature indicator,TTI)作为有效的监测工具已被应用于预估各类生鲜食品的剩余货架期.TTI是用于记录食品时间和温度历史的装置,它是利用时间和温度的累积效应产生的不可逆现象所实现的,有助于确保食品的质量和安全,但是由于其成本高、性能...     

基于自动脉冲TIG焊的核级阀门管道焊接工艺

针对核电厂运行期间核一级手动截止阀唇边焊易发生泄露的风险,要求阀门需要进行整体更换,分别对核级阀门两种规格的接头开展自动脉冲TIG焊接工艺研究,并对焊后的试件进行渗透、X射线探伤等无损检验和拉伸、弯曲、金相、化学分析和晶间腐蚀等破坏性检验。试验结果表明,壁厚2.77 mm的焊接接头拉伸力平均值为564 MPa,断后伸长率平均值为39.25%;壁厚8.7 mm的焊接接头拉伸力平均值为612 MPa,断后伸长率平均值为46.75%,两种壁厚的焊接接头均具有良好的力学性能,面弯试验和背弯试验均未发现裂纹,弯曲性能良好;壁厚2.77 mm接头的金相组织主要是板条状铁素体,壁厚8.7 mm接头的金相组织主要以树枝状铁素体为主;两种壁厚的焊接接头中熔敷金属的化学成分经检验均满足技术条件的规定;采用弯曲法进行晶间腐蚀试验,经检验两种规格的接头均无晶间腐蚀倾向。     

Extending the metal to insulator transitions of rare-earth nickelates towards low temperature ranges

Although the d-band correlated rare-earth nickelates (ReNiO₃) exhibit broadly adjustable metal to insulator transitions (MIT) that enables emerging correlated electronic applications, it is yet difficult to regulate their associated critical temperature (T_MIT) below 100 K. Herein, we extend the lower limit in T_MIT of ReNiO₃ down to 83 K while maintaining an abrupt switch in resistivity via partial La-substitution of PrNiO₃. The near edge X-ray fine structure analysis and density function theory calculations indicate the strengthening in the metallic orbital configuration and reduction in the ground state band gap via La-substitution of Re in NdNiO₃ and PrNiO₃. In contrast, analogous Ce substitution cannot reduce the T_MIT of ReNiO₃ owing to its valance variability toward +4, while La partial substitution of ReNiO₃ with middle or heavy rare-earth (e.g., Sm) easily disturb the co-occupation of the Re-site by the two rare-earths as one dispersive phase.     

Semiconducting Transport in Pb10−XCux(PO4)6O Sintered from Pb2SO5 and Cu3P

The recent claim on the discovery of ambient-pressure room-temperature superconductivity in Cu-doped lead-apatite has attracted sensational attention. The intriguing compound has been fabricated by sintering lanarkite (Pb₂SO₅) and copper(І) phosphide (Cu₃P). To verify this exciting claim, Pb₂SO₅, Cu₃P, and finally the modified lead-apatite Pb_10−xCu_x(PO₄)₆O have been successfully synthesized. Detailed electrical transport and magnetic properties of these compounds are systematically analyzed. It turns out that Pb₂SO₅ is a highly insulating diamagnet and Cu₃P is a paramagnetic metal. The obtained nominal Pb_10−xCu_x(PO₄)₆O compound sintered from Pb₂SO₅ and Cu₃P exhibits semiconductor-like transport behavior with a large room-temperature resistivity of ≈1.94 × 10⁴ Ω·cm, although the major phase of the compound shows consistent X-ray diffraction spectrum with the previously reported structure data. In addition, when a Pb_10−xCu_x(PO₄)₆O pellet pressed from uniformly ground powder is located on top of a commercial Nd₂Fe₁₄B magnet at room temperature, no repulsion can be felt and no magnetic levitation is observed either. The large difference in electrical and magnetic properties between the compounds and the previously reported compounds might be induced by distinct fine crystallographic structures, diverse multi-phase distributions, and different concentrations of impurity phases such as Cu₂S, all of which deserve further study.     

Topotactic Transition: A Promising Opportunity for Creating New Oxides

Topotactic transition is a structural phase change in a matrix crystal lattice mediated by the ordered loss/gain and rearrangement of atoms, leading to unusual coordination environments and metal atoms with rare valent states. As early as in 1990s, low temperature hydride reduction is utilized to realize the topotactic transition. Since then, topological transformations are developed via multiple approaches. Especially, the recent discovery of the Ni-based superconductivity in infinite-layer nickelates has greatly boosted the topotactic transition mean to synthesizing new oxides for exploring exotic functional properties. In this review, a detailed and generalized introduction is provided to oxygen-related topotactic transition. The main body of the review includes four parts: the structure-facilitated effects, the mechanism of the topotactic transition, some examples of topotactic transition methods adopted in different metal oxides (V, Mn, Fe, Co, Ni) and the related applications. This study is to provide timely and thorough strategies to successfully realize topotactic transitions for researchers who are eager to create new oxide phases or new oxide materials with desired functions.