扩展“G函数”模型在火山岩测试压裂参数解释中的应用——以大庆油田徐深气田为例

松辽盆地大庆油田徐深气田火山岩储气层由于天然裂缝发育及局部构造变化大,从而导致压裂中出现高滤失、高停泵压力梯度以及近井高摩阻等疑难问题。为进一步提高疑难储层改造的施工成功率,基于以往对徐深气田火山岩储层测试压裂方法（传统“G函数”模型,二维）研究的成果,建立了更适合该气田的火山岩储层压裂参数解释的扩展“G函数”模型（三维）。选取11口井共31层段进行现场实验,包括了天然裂缝较发育、天然裂缝极其发育、低滤失、高度衰退、复合型５种“G函数”图版类型,其中仅有4个层设计加砂符合率低于80%,其余27层设计加砂符合率均高于80%。现场应用情况的统计结果表明,新理论模型使得压裂设计加砂符合率由72.4%提高到87.1%,从而更好地解决了火山岩难压储层改造成功率低的问题,为该类储层压裂成功率的提高提供了理论基础,对水力压裂技术在裂缝性火山岩储层中的应用具有重要意义。     

硫粉改性Mo基耐硫甲烷化催化剂

采用常规的H2S/H2混合气硫化方式和硫粉改性的硫化方式对15%(w)Mo/Al2O3和20%(w)Mo/25%(w)CeO2-Al2O3催化剂进行硫化处理,并考察了两种硫化方式处理的催化剂的耐硫甲烷化性能。实验结果表明,在600℃下,硫粉改性硫化处理的15%(w)Mo/Al2O3和20%(w)Mo/25%(w)CeO2-Al2O3催化剂上的CO转化率分别为60.3%和71.0%,而常规硫化方式处理的两种催化剂上的CO转化率仅为49.8%和61.2%,硫粉改性硫化的效果明显优于常规硫化。结合N2吸附-脱附、XRD、Raman光谱、XRF等表征手段对两种不同硫化方式处理的催化剂进行物相和结构分析的结果表明,两种硫化方式均能实现MoO3的完全转化,而硫粉改性的硫化方式可以促进Mo的硫化,提高n(S)∶n(Mo),使催化剂中出现晶态的MoS2。     

Strongly Coupled Nickel–Cobalt Nitrides/Carbon Hybrid Nanocages with Pt‐Like Activity for Hydrogen Evolution Catalysis

Designing non‐precious‐metal catalysts with comparable mass activity to state‐of‐the‐art noble‐metal catalysts for the hydrogen evolution reaction (HER) in alkaline solution still remains a significant challenge. Herein a new strongly coupled nickel–cobalt nitrides/carbon complex nanocage (NiCoNzocage) is rationally designed via chemical etching of ZIF‐67 nanocubes with Ni(NO₃)₂ under sonication at room temperature, following nitridation. The as‐prepared strongly coupled NiCoN/C nanocages exhibit a mass activity of 0.204 mA µg^?1 at an overpotential of 200 mV for the HER in alkaline solution, which is comparable to that of commercial Pt/C (0.451 mA µg^?1). The strongly coupled NiCoN/C nanocages also possess superior stability for the HER with negligible current loss under the overpotentials of 200 mV for 10 h. Density functional theory (DFT) calculations reveal that the excellent HER performance under alkaline condition arises from the robust Co²⁺→Co⁰ transformation achieved by strong (Ni, Co)? N‐bonding‐induced efficient d‐p‐d coupled electron transfer, which is a key for optimal initial water adsorption and splitting. The high degree of amorphization urges the C‐sites to be an electron‐pushing bath to promote the inter‐layer/sites electron‐transfer with loss of the orbital‐selection‐forbidden‐rule, which uniformly boosts the surface catalytic activities up to a high level independent of the individual surface active sites.     

Stimulated emission from distyrylbenzene derivative crystals grown by vapor deposition

Narrowed spectra at 452 nm from a thin platelike crystal of distyrylbenzene derivative, 2,5-diphenyl-1,4-distyrylbenzene with two trans double bonds (trans-DPDSB) grown by vapor deposition, are observed. The trans-DPDSB crystal is irradiated by the third harmonic (355 nm) of a Nd:YAG laser. The FWHM of the narrowed spectra can reach 6 nm for the crystal when the pumping energy is 400 microJ/pulse. The threshold value for an optically pumped laser is approximately 350 microJ/pulse.     

伴随同化技术在渤、黄海生态模式中的应用:控制变量的选取与孪生实验

在渤、黄海海域建立了物理海洋模型与NPZD生态模型的耦合模型,就伴随同化技术应用中如何从众多模型参数中选择控制变量的难题做了深入研究.研究发现,对于渤、黄海海区的NPZD模型,除了用传统的方法选取控制变量之外,代价函数关于模型参数的梯度信息也可以作为选取控制变量的标准之一,这从另一个角度解决了如何确定控制变量的问题.另外,通过孪生实验验证了在渤、黄海NPZD生态模式中使用伴随同化技术同化水色遥感数据的可行性,这为以后将水色卫星遥感数据同化到海洋生态模型中奠定了基础.     

Properties of implanted PET by W ion using MEVVA implantation

Polyethylene terephthalane (PET) has been modified with W ions from a metal vapour arc source (MEVVA). W ions were implanted at 136 keV to doses ranging from 5×10¹⁵ to 2×10¹⁷/cm². The surface of the implanted PET darkened with increasing ion dose, when the metal ion dose is greater than 1×10¹⁷ cm⁻² the colour changed to metallic bright. The surface resistance obviously decreases with increasing dose. The resistivity is stable after long-term storage. TEM photos revealed the presence of W nanometer particles on the surface resulting from the high does implantation. The depth of implanted layer is approximately between 180 and 100 nm for W-implanted PET to doses of 2×10¹⁷/cm² and 5×10¹⁶/cm², respectively. The conductivity and wear resistance have been improved significantly due to W ion implantation. It can be seen that nanometer particles of W precipitation, and carbides have been formed in the implanted layer. The nano-hardness of the implanted PET has been measured by a nano-indenter. The results show that the surface hardness, modulus and wear resistance could be increased.     

Synthesis, characterization and catalytic activity of ordered macroporous silicas functionalized with organosulfur groups

Hybrid three-dimensionally ordered macroporous (3DOM) SiO₂-SO₃H materials with different S/Si ratio have been prepared by colloidal crystal templating method. The process involved preparation of 3DOM SiO₂-SH materials by co-condensation of (3-mercaptopropyl)triethoxysilane and tetraethoxysilane via sol-gel transformation, and following oxidation of -SH group to -SO₃H group by H₂O₂. Materials were characterized by scanning electron microscopy (SEM), Fourier transform infra-red spectrometer (FTIR), thermogravimetric analysis (TGA), and nitrogen adsorption measurement. SEM observation shows that the macropores are highly ordered with a typical “surface-templated” structure. The surface area of 3DOM SiO₂-SH material is 25.1 m²/g and SiO₂-SO₃H material is 18.6 m²/g. Catalytic activity test shows that 3DOM SiO₂-SO₃H materials possess a high activity for the esterification of acetic acid and n-butanol, and the activity is increased with the amount of sulfur in the materials. This study provided significant results for developing new application of 3DOM materials.     

一种基于USB 2.0的实时数据采集系统设计与实现

结合当前实时数据采集系统面临的问题和USB总线的突出优点,提出了一种基于USB 2.0总线技术的实时数据采集系统的设计及具体实现方法.根据要设计的系统的要求,给出了硬件电路框图,通过比较,选取了A/D芯片和USB通信接口芯片,并对Cypress公司的EZ-USB FX2芯片做了简单介绍.围绕EZ-USB FX2芯片,进行系统软件包括固件程序、设备驱动程序和应用软件的开发设计,详细介绍了设备固件程序的设计,给出了流程图和主要的代码.并对基于USB总线的数据采集系统的未来发展做了展望.     

一种TFT LCD数字源驱动芯片的设计

分析了多晶硅薄膜晶体管(poly-Si TFT)有源矩阵驱动的结构和源驱动器的驱动原理及基本构成,并针对分辨率为800×600的64级灰度的VGA显示屏,采用分块矩阵的方法使数据转换频率降低到原来的1/10,在此基础上对传统的源驱动电路进行了改进,使DAC电路的数目大大减少,从而减小芯片面积,降低整个芯片的功耗。对电路采用Cadence进行仿真,给出了逻辑部分工作时序波形。