Suppressed Lattice Disorder for Large Emission Enhancement and Structural Robustness in Hybrid Lead Iodide Perovskite Discovered by High-Pressure Isotope Effect

The soft nature of organic–inorganic halide perovskites renders their lattice particularly tunable to external stimuli such as pressure, undoubtedly offering an effective way to modify their structure for extraordinary optoelectronic properties. Here, using the methylammonium lead iodide as a representative exploratory platform, it is observed that the pressure-driven lattice disorder can be significantly suppressed via hydrogen isotope effect, which is crucial for better optical and mechanical properties previously unattainable. By a comprehensive in situ neutron/synchrotron-based analysis and optical characterizations, a remarkable photoluminescence (PL) enhancement by threefold is convinced in deuterated CD₃ND₃PbI₃, which also shows much greater structural robustness with retainable PL after high peak-pressure compression–decompression cycle. With the first-principles calculations, an atomic level understanding of the strong correlation among the organic sublattice and lead iodide octahedral framework and structural photonics is proposed, where the less dynamic CD₃ND₃⁺ cations are vital to maintain the long-range crystalline order through steric and Coulombic interactions. These results also show that CD₃ND₃PbI₃-based solar cell has comparable photovoltaic performance as CH₃NH₃PbI₃-based device but exhibits considerably slower degradation behavior, thus representing a paradigm by suggesting isotope-functionalized perovskite materials for better materials-by-design and more stable photovoltaic application.     

富芳烃重油组分结构调变对中间相沥青形成的影响机制

对重油富芳烃组分转化为次生沥青及其氢化改性沥青的热转化行为进行了比较，并对热转化过程中体系化学结构组成特征对中间相形成的影响进行了研究。采用红外光谱及氢核磁共振波谱，对比分析了次生沥青及其氢化改性沥青的化学结构组成特征；借助偏光显微镜、X射线衍射，考察了两体系中间相沥青的形成过程。结果表明：控制体系短烷基侧链含量可有效抑制过度炭化的发生，提高炭化产物的微观有序度；短烷基侧链可以持续稳定释放出小分子自由基，对大分子自由基反应进行调控，显著提升炭化产物微观结构的均一性。     

蜀南地区富有机质页岩孔隙结构及超临界甲烷吸附能力

以蜀南地区龙马溪组下部富有机质页岩为研究对象，通过场发射扫描电镜（FE-SEM）、低压氩气吸附实验和重力法高压甲烷吸附实验，研究页岩孔隙结构特征及超临界状态下页岩储层的甲烷吸附能力，并讨论了页岩孔隙结构对甲烷吸附能力的影响。研究表明，蜀南地区龙马溪组富有机质页岩主要发育有机质孔隙，页岩孔隙结构非均质性强，比表面积为16.846~63.738 m²/g，孔体积为0.050~0.092 cm³/g，微孔和介孔贡献页岩90%以上的比表面积，介孔和宏孔贡献页岩90%以上的孔体积。甲烷在地层条件下处于超临界状态，过剩吸附曲线在约12 MPa时出现极大值，随后开始下降。使用修正过的四元Langmuir-Freundlich （L-F）方程拟合高温甲烷过剩吸附曲线，拟合效果较好，相关系数大于0.997。页岩饱和吸附量为0.067 0~0.220 2 mmol/g，不同页岩样品吸附能力差异明显。海相富有机质页岩中，随着有机质含量的增大，有机质孔隙数量增多，且页岩中微孔比例增大，微孔的吸附能力远大于介孔和宏孔，故页岩吸附能力增强。有机质含量是影响蜀南地区海相富有机质页岩孔隙结构和甲烷吸附能力的主要因素。     

压裂管汇无损检测方法改进

:按照现有无损探伤检验标准检验合格的压裂管汇在压裂作业时出现了管件刺漏、爆裂等情况。分析了压裂管汇中管件结构的特点和现有的无损检测方法的适用性。增加了管件的检测部位,改进了检测方法,并研制出了能检测不同形状和尺寸管件的超声波探头和比对试件。采用改进的无损检测方法,检测出不合格管件数增加44.9%。新增加检测部位后,检测出不合格管件数增加63.7%。目前已应用改进的无损检测方法1 a多,在压裂作业时未出现高压管件刺漏或爆裂情况。     

Headspace fingerprinting approach to identify the major pathway influencing volatile patterns of vinasse-cured duck processed by high pressure,as well as its impact on physicochemical and sensory attributes

As a decisive attribute, flavour could be influenced by HP treatments through multiple physical and chemical pathways within the high pressure (HP)-assisted meat curing process. This investigation aimed to identify the major pathway influencing volatile flavour patterns of two representative vinasse-cured duck (VCD) products with HP treatments (150–300 MPa/15 min), including wet and dry types, by employing headspace fingerprinting as an untargeted approach. Results suggested that HP treatments greatly lowered moisture contents and increased Warner-Bratzler shear force and thiobarbituric acid reactive substances of the cured samples. According to multivariate models, the volatile flavour patterns of the HP-processed VCD could be clearly separated from the unprocessed samples, but the VCD pressurised at different intensities represented similar volatile fingerprinting, which was validated by e-nose analysis. The discriminant analysis (OPLS-DA) model outlined vinasse-derived ethanol, acetic acid, 3-methyl-1-butanol, 2-methyl-1-butanol, phenethyl alcohol and 2-methyl-3-octanone as the major discriminant aromas across the unpressurised and pressurised samples.     

铬酸钠碳化母液制备氢氧化铬工艺优化 及三氧化二铬粒度分布的影响

研究了利用铬酸钠碳化母液制备氢氧化铬工艺优化及三氧化二铬粒度分布的影响，主要考察了恒温温度、氢氧化铬洗涤方式对产品质量的影响；还考察了在固定煅烧条件下，铬酸钠含量对三氧化二铬颗粒形貌的影响以及铬酸钠碳化母液碳化率与三氧化二铬粒度分布的关系。结果表明，随着铬酸钠碳化母液碳化率的提升，Cr（Ⅵ）达到最大还原率时所需恒温温度下降，经过3次洗涤的氢氧化铬滤饼煅烧后铬酸钠质量分数为13%~15%，制备的三氧化二铬呈类球体，颗粒粒径均匀，洗涤烘干后各项参数指标均优于GB/T 20785—2006《氧化铬绿颜料》。通过增加原料碳化率，三氧化二铬颗粒的中位径D50随之增大，在碳化率为39.87%时制得的三氧化二铬中位径D50为 3.13 μm，粒度分布为典型的正态分布，其特征粒径值均符合高端氧化铬绿产品的技术要求。     

Preparation and Adsorption Properties of Biomass Activated Carbon from Ginger Stems

Biomass activated carbon(BAC) was produced from ginger stems by carbonization and activation presented high specific surface areas and mesoporous structures. The carbonization temperature of the ginger stems were controlled within 500～900℃. The optimal carbonization condition is as follows: carbonization temperature of 700℃, carbonization time of 6 h. The determined optimum activation condition is: temperature of 800℃, activator of KOH and carbonized product/alkali ratio of 1:4(w/w). The carbonization yield, BAC yield and Brunauer-Emmett-Teller(BET) surface area were measured and the adsorption performance of BAC to nitrogen was investigated. The results showed that the nitrogen adsorption isotherm curve was as type I isotherm. It was finally determined that the BET surface area was 660 m~2/g under the abovementioned optimal conditions of carbonization and activation. The FESEM analysis indicates that the obtained BAC is of micropore structure.