5G NTN关键技术研究与演进展望

5G非地面网络（non-terrestrial network,NTN）技术是5G通信系统面向卫星通信和低空通信等新应用场景的重要技术，标志着5G技术应用从陆地通信走向了空间通信。首先分析了5G NTN和地面5G的差异点，包括网络架构、时频同步、HARQ和移动性管理等。进而介绍了3GPP Release 17的5G NTN标准进展及关键技术点与3GPP Release 18的5G NTN增强技术。最后展望了未来空、天、地一体化的技术演进。通过对5G NTN技术研究和标准分析，明确了5G和卫星通信融合的技术路线，并为后续6G空、天、地融合系统研究和设计提供基础。     

Preparation of P(St-NMA) microsphere inks and their application in photonic crystal patterns with brilliant structural colors

Patterned photonic crystals with structural colors on textile substrates have attracted a special attention due to the great advantages in application, which currently become a research hot-spot. This study utilized an ink-jet printing technology to prepare high-quality photonic crystal patterns with structural colors on polyester substrates. The self-assembly temperature of poly(styrene-N-methylol acrylamide) (P(St-NMA)) microspheres set to construct photonic crystals were deeply optimized. Moreover, the structural colors of prepared photonic crystal patterns were characterized and evaluated. When the mass fraction of P(St-NMA) microspheres was 1.0 wt.%, the pH value ranged from 5 to 7, and the surface tension was in the range of 63.79 to 71.20 mN/m, inks could present the best print performance. At 60 °C, prepared P(St-NMA) microsphere inks were good for printing to obtain patterned photonic crystals with regular arrangement and beautiful structural colors. Specifically, photonic crystals with different colors could be constructed by regulating the diameter of microspheres in inks, and prepared structural colors exhibited distinct iridescent phenomenon. The present results could provide a theoretical basis for the industrial realization of patterned photonic crystals by ink-jet printing technology.     

蒙古国稀土矿地质特征及资源潜力

蒙古国蕴含丰富的稀土矿资源。本文通过对蒙古国成矿地质背景及典型稀土矿床进行研究,将蒙古国稀土矿床划分为碱性花岗岩型、碳酸岩型、伟晶岩型、离子吸附型、稀土砂矿型等5种成因类型,其中碱性花岗岩型和碳酸岩型是蒙古国稀土矿的主要成因类型;将蒙古国划分为3个稀土成矿省和7个稀土成矿带,并结合蒙古国成矿地质背景及矿产开发情况,初步划分出图瓦-库苏古尔稀土矿潜力区、肯特稀土矿潜力区和达兰扎达嘎德稀土矿潜力区共3处稀土矿勘查开发潜力区。     

Bacillus sphaericus DS11蛋白酶基因osp在Bacillus subtilis的异源表达及酶学性质研究

将Bacillus sphaericus 2297蛋白酶基因osp在Bacillus subtilis WB800异源表达,并进行纯化和酶学性质研究。以Bacillus sphaericus DS11基因组DNA为模板,扩增osp基因,构建重组质粒pMA0911-His_6-osp,重组质粒转化Bacillus subtilis WB800获得重组表达菌株Bacillus subtilis WB800-pMA0911-His_6-osp。利用镍离子柱亲和层析纯化重组酶至电泳纯。重组酶最适催化温度和pH值分别为40℃和pH 8.0,在20℃～30℃下保温10 h保持80%以上酶活力,在pH 7.0～9.0处理24 h保持60%以上酶活力;Sr~(2+)、K~+、Mg~(2+)对酶活有促进作用,Fe~(3+)、Ba~(2+)、Ca~(2+)对酶活有抑制作用;重组蛋白酶在极性常数为0.8～3.1的有机溶剂中孵育6 d后保持53%以上的酶活力。     

Microstructural characteristics of as-forged and β-air-cooled Zr–2.5Nb alloy

Multiple characterization and analysis techniques including electron backscatter diffraction (EBSD), electron channeling contrast (ECC) imaging, transmission electron microscopy (TEM) and microhardness test were jointly employed to investigate microstructural characteristics such as local composition, morphology, grain boundary characteristics and interphase orientation relationship of a forged Zr–2.5Nb alloy before and after β-air-cooling. Results show that the as-forged specimen is composed of equiaxed and lamellar α grains and continuous net-like β-Zr films. After the β-air-cooling, the microstructure of the specimen is featured by basket-weave Widmanstätten structure, in which the inter-α-plate second phases are nanoscale β-Zr. Analyses for crystallographic orientations reveal that the Burgers relationship has been strictly followed during the β→α cooling. Compared to the as-forged specimen, the hardness of the β-air-cooled specimen is higher, which could be attributed to the decreased structural sizes of both α and β phases, and the increased fraction of high angle boundaries as well.     

一种胶体电荷测定装置的改进

介绍了目前应用广泛的胶体电荷测定仪,针对其测量样品池提出一种改进方式。该装置在基于流动电流测量原理的前提下,引进数字数据蓝牙传输和无线供电的新技术。通过改变微弱流动电流的处理方式与信号传输模式,使流动电流信号在测量过程中减少损失,从而保证胶体电荷测量更加准确和方便。     

俄罗斯西伯利亚地区重要矿产资源现状与潜力

西伯利亚地区是俄罗斯重要的矿产资源基地,油气资源是东西伯利亚-太平洋石油管道运输系统的主要供应原料,煤、铀、铜、镍、铂、钼、铅和锰等矿产的储量和开采量均居全俄第一位。煤矿资源远景区集中在克拉斯诺亚尔斯克边疆区南部、伊尔库茨克州西南部和科迈罗沃州;铀矿资源远景区分布在外贝加尔边疆区、布里亚特共和国等地;铜、镍、铂族金属远景区集中于诺里尔斯克矿区,铅锌资源远景区位于霍洛德宁矿床、奥泽尔矿床和戈列夫矿床等地,锰矿资源远景区集中于乌辛斯克矿床。本区矿产资源潜力巨大,开发程度较低,区域发展与我国振兴东北地区战略可有效对接,具有较强的互补性,我国企业应积极参与西伯利亚地区矿产资源开发,并加强在资源潜力区及边境地区基础设施建设方面的合作。     

基于聚类分析的浓缩苹果汁风味品质分析与评价

通过对浓缩苹果汁主要风味物质进行分析,建立其风味品质的客观评价方法,为生产者合理调整工艺提供参考。分别选取风味较好和风味较差的浓缩苹果汁样品,对其挥发性风味物质、有机酸、氨基酸、糖类等主要风味物质进行分析,采用主成分分析、因子分析综合打分、聚类分析等方法筛选出能够有效区分不同风味品质浓缩苹果汁样品的主要风味化合物。选取12批次浓缩苹果汁样品,检测样品中39种主要挥发性风味物质、14种主要氨基酸、6种主要有机酸以及4种主要的糖类等风味物质。根据因子分析综合打分结果,从29种组合中,筛选出能够区分浓缩苹果汁风味的5种主要风味物质,分别为天冬氨酸、丝氨酸、蛋氨酸、果糖和葡萄糖。利用不同年份的8个批次浓缩苹果汁样品对该结果进行了验证,结果表明,这5种风味物质能够有效区分A、B两类浓缩苹果汁。利用筛选出的5种主要风味物质,能够对浓缩苹果汁风味品质进行客观、准确的判别。     

KDP/DKDP倍频晶体主截面定位方法

KDP/DKDP倍频晶体是惯性约束聚变系统中的关键元件,其主截面方向与晶体相位匹配角、晶体吸收系数紧密相关。为了实现KDP/DKDP倍频晶体主截面方向的高精度定位,本文提出一种光强测量间接定位方法。通过激光器结合稳功率仪及半波片输出稳定线偏振光,同时旋转相互正交的起偏器与检偏器可获得晶体的最佳消光位置即为主截面方向。推导了该测量系统光强的琼斯矩阵模型,给出了光强与起偏器、检偏器角度间的关系表达式。采用最小二乘方法拟合经过起偏器、倍频晶体及检偏器的光强变化曲线,从而可精确定位倍频晶体主截面的方向。通过计算机仿真模拟和实验验证了该方法的正确性和可行性。实验表明,该方法定位的重复测量精度优于0.02°,满足惯性约束聚变系统中KDP/DKDP倍频晶体主截面的定位控制精度要求。