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表观扩散系数和动态对比增强MRI的定量参数在宫颈癌病理分级中的价值

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临床放射学杂志 2024年第7期43卷 1159-1163页

作者：白志强张翔邓刊史洁中山大学孙逸仙纪念医院广州510120 飞利浦临床技术科研部广州510120

目的探讨表观扩散系数(ADC)和定量动态对比增强磁共振成像(qDCE-MRI)在预测宫颈癌病理分级中的价值。方法回顾性分析中山大学孙逸仙纪念医院2017年7月至2021年12月95例经手术病理确诊为宫颈癌的初诊患者的影像资料,所有患者术前均行常规... 详细信息

目的探讨表观扩散系数(ADC)和定量动态对比增强磁共振成像(qDCE-MRI)在预测宫颈癌病理分级中的价值。方法回顾性分析中山大学孙逸仙纪念医院2017年7月至2021年12月95例经手术病理确诊为宫颈癌的初诊患者的影像资料,所有患者术前均行常规MRI、扩散加权成像(DWI)及qDCE-MRI检查。分析定量参数容积转运常数(K^(trans))、速率常数(K_(ep))、血管外细胞间隙容积分数(V_(e))、血浆容积分数(V_(p))和ADC在不同病理级别宫颈癌之间的差异性和相关性。分析各参数预测G1/2和G3宫颈癌的效能。结果K^(trans)和K_(ep)均与肿瘤病理分级呈正相关(r=0.323,P=0.001;r=0.455,P<0.001)。K^(trans)和K_(ep)在G3肿瘤和G1/2肿瘤之间的差异具有统计学意义(Z=-2.769,P=0.006;Z=-4.321,P<0.001)。K^(trans)预测G3和G1/2肿瘤的敏感度、特异度和准确率分别为60.8%,72.7%和66.3%。Kep预测G3和G1/2肿瘤的敏感度、特异度和准确率分别为82.4%,63.6%和73.7%。结论K^(trans)和K_(ep)与宫颈癌病理分级呈正相关,并且均可用于鉴别G3和G1/2肿瘤。

关键词：宫颈癌病理分级磁共振成像动态对比增强扩散加权成像

1T-MoSe_(2)负载过渡金属单原子电催化氮气还原合成氨的理论研究

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Chinese Journal of Chemical Physics 2024年第1期37卷 109-115,I0103-I0111,I0118,I0119页

作者：孙阿强秦明鑫朱少通周颖白志强张文华中国科学技术大学精准智能化学重点实验室合肥230026 中国科学技术大学合肥微尺度物质科学国家研究中心合肥230026 河南师范大学物理学院新乡453007

寻找稳定高效的电催化氮气还原合成氨单原子催化剂受到了理论研究的广泛关注.本文采用密度泛函理论计算对二维1T-MoSe_(2)负载的18种过渡金属单原子催化剂(TM@1T-MoSe_(2),TM=V,Cr,Mn,Fe,Co,Ni,Nb,Mo,Tc,Ru,Rh,Pd,Ta,W,Re,Os,Ir,Pt)的稳定性以及电催化氮气还原合成氨活性和选择性进行了理论评估.计算结果表明,W@1T-MoSe_(2)是最具潜力的电催化氮气还原合成氨单原子催化剂,三个N2分子共吸附于W@1T-MoSe_(2),电催化氮气还原合成氨反应通过远端路径进行,理论限制电位为-0.23 V.此外,N2在W@1T-MoSe_(2)上的多重吸附有效抑制了析氢反应,提高了电催化氮气还原合成氨选择性.这项研究为基于1T-MoSe_(2)的新型单原子催化剂在电催化氮气还原合成氨方面的开发提供了理论依据.

关键词：密度泛函理论单原子催化剂氮气电还原选择性活性

Enhanced nitrogen electroreduction performance by the reorganization of local coordination environment of supported single atom on N(O)-dual-doped graphene

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Nano Research 2023年第7期16卷 9099-9106页

作者： zhiqiang bai Wenhua Zhang Yufang Liu School of Physics Henan Normal UniversityXinxiang 453007China School of Cable Engineering Henan Institute of TechnologyXinxiang 453000China Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy Conversion and Synergetic Innovation Centre of Quantum Information&Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Developing stable and efficient catalysts for the electroreduction of nitrogen remains a huge challenge and single atom catalysts(SACs)are expected to achieve relatively high ammonia selectivity at low applied *** on density functional theory calculations,the potential application of 27 single transition metal(TM=Sc-Zn,Y-Ag,Hf-Au)atoms supported by N(O)-dualdoped graphene(TM-O_(2)N_(2)/G)for the electroreduction of nitrogen is intensively *** low nitrogen coverage,W(Mo,Nb,Ta)-O_(2)N_(2)/G are predicted to yield low ammonia selectivity(<13%)at limiting-potential of-0.58,-0.53,-0.56,and-0.76 V starting from adsorbed nitrogen with side-on mode,*** the increasing N_(2)coverage,the TM-O_(2)N_(2)/G is reconstructed as TM-(N_(2))2N_(2)/*** electroreduction of nitrogen proceeds from end-on adsorbed nitrogen molecule with high ammonia selectivity,and the limiting-potentials are theoretically predicted as-0.20,-0.40,-0.29,and-0.21 V on W(Mo,Nb,Ta)-(N_(2))2N_(2)/G,*** is suggested that utilizing the reorganization of local coordination environments of SACs by high coverage of reactant molecules under reaction condition can not only enhance the activity at lower limiting-potential but also improve the ammonia selectivity.

关键词： nitrogen reduction reaction single atom catalysis local structure reorganization doped graphene electroreduction

Palaeogeographic Position of the South China Plate During the Early-Middle Devonian

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 19-26页

作者： bai zhiqiang bai Shunliang Department of Geology, Peking University, Beijing Department of Geology Peking University Beijing

In Guangxi, the Lower-Middle Devonian boundary beds yield abundant corals, brachiopods,stromatoporoids and conodonts. The former three were common in tropical and subtropical zones, while thelast occurred only round the equator. This reveals that the South China Plate in the Early-Middle Devonianwas at or near the equator, which was also supported by palaeomagnetic study giving the palaeolatitude of theGuangxi Region at the time to be 0°36′N.

关键词： Palaeogeographic Position of the South China Plate During the Early-Middle Devonian

新型瓦斯抽采自膨胀护孔抗压花管的研制与应用

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矿业研究与开发 2024年第1期44卷 161-167页

作者：王振锋白志强王宇王琼霄曹良超河南理工大学能源科学与工程学院河南焦作市454003

对松软煤层进行穿层瓦斯抽采时,在采动影响下,易发生钻孔收缩变形和坍塌、花管堵塞等问题,导致瓦斯抽采效率低、抽采周期延长,甚至需要补孔进行二次瓦斯抽采。为此,研究一种新型自膨胀护孔抗压花管。新型自膨胀花管外围的弹簧钢片在钻... 详细信息

对松软煤层进行穿层瓦斯抽采时,在采动影响下,易发生钻孔收缩变形和坍塌、花管堵塞等问题,导致瓦斯抽采效率低、抽采周期延长,甚至需要补孔进行二次瓦斯抽采。为此,研究一种新型自膨胀护孔抗压花管。新型自膨胀花管外围的弹簧钢片在钻孔内膨胀成球体,可有效抵御钻孔变形,弹簧钢片外围的钢丝网布可阻挡煤体坍塌,防止花管堵塞,从而在抽采中后期使煤层与花管之间仍有较大的空间供瓦斯径向流动与球向流动,有助于瓦斯由吸附态转化为游离态,提高瓦斯抽采效率。现场试验表明,在瓦斯抽采初期,采用常规花管的对照组与采用自膨胀花管的试验组相比较,平均瓦斯抽采浓度接近,但在抽采50d之后的中后期,试验组的瓦斯抽采浓度仍能保持在20%以上,瓦斯涌出量是对照组瓦斯抽采浓度的4倍以上,因此,新型自膨胀花管具有较好的应用价值。

关键词：瓦斯抽采钻孔自膨胀花管瓦斯涌出量瓦斯抽采浓度数值模拟

Recent approach to Buchia biostratigraphy from the Tethyan Himalaya area,China

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Frontiers in Biology 2006年第2期1卷 213-218页

作者： bai zhiqiang Xia Zunyi Department of Geology Peking UniversityBeijing 100871China

Recent collections from six sections in Lanongla area,Tethyan Himalaya allow the establishment of four buchia *** ascending order,they are Buchia-Buchia spitiensis,Buchia masquensis-Buchia rugasa,Buchia blanfordiana,Buchia piochii and Buchia subokensis *** Buchia assemblages first demonstrate that not only the Upper Jurassic strata but also the highest Buchia assemblage-Buchia subokensis,which appeared in Lower Cretaceous strata all over the world are present in Lanongla *** first records the highest Buchia assemblage in Lanongla area.

关键词： Buchia Upper Jurassic Lower Cretaceous Tethyan Himalaya area

Phase behavior and interfacial properties of symmetric polymeric ternary blends A/B/AB

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Science China Chemistry 2013年第12期56卷 1710-1721页

作者： LIU XiaoHan bai zhiqiang YANG KeDa SU JiaYe GUO HongXia Beijing National Laboratory for Molecular Sciences Joint Laboratory of Polymer Sciences and Materials State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences

In this paper, the phase behavior and interracial properties of symmetric ternary polymeric blends A/B/AB are studied by dissipative particle dynamics （DPD） simulations. By using the structure factor and nematic order parameter, we carefully characterized the diversified phases and phase transitions, and established the phase diagram of such symmetric ternary blends. It can be generally divided into four regions： disordered phase （DIS） region at high temperature, ordered lameUar phase （LAM） region, bicontinuous microemulsion （BμE） channel and phase-separated phase （2P） region at low temperature with the increase of the total volume fractions of homopolymers φn, which shows good accordance with that in previous experimental and theoretical reports. Furthermore, we calculated the elastic constants of 2P and LAM phase, and discussed the transition mechanisms from 2P and LAM to BμE phase, respectively. The results show a direct relevance between the phase transitions and the change of interfacial properties. Finally, we also demonstrate that the B,uE channel becomes narrower in lower temperature caused by the temperature dependence of interfacial properties of ternary blends.

关键词： symmetric ternary blend phase behavior bicontinuous microemulsion dissipative particle dynamics

针刀联合痛点注射治疗神经根型颈椎病临床观察

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中医临床研究 2024年第3期16卷 90-92页

作者：郭永富白志强温建民北京市第一中西医结合医院北京100060 北京望京医院北京100102

目的:探讨针刀联合痛点注射治疗神经根型颈椎病的临床效果。方法:选取2019年2月―2021年12月北京市第一中西医结合医院骨科门诊60例神经根型颈椎病患者,随机分为治疗组(30例)和对照组(30例)。对照组采用针刀治疗,治疗组采用颈部压痛点... 详细信息

目的:探讨针刀联合痛点注射治疗神经根型颈椎病的临床效果。方法:选取2019年2月―2021年12月北京市第一中西医结合医院骨科门诊60例神经根型颈椎病患者,随机分为治疗组(30例)和对照组(30例)。对照组采用针刀治疗,治疗组采用颈部压痛点注射即引起上肢麻木疼痛的责任节段关节突关节旁注射联合针刀治疗。观察两组临床疗效指标。结果:治疗组总有效率显著高于对照组,P <0.01。治疗后两组症状、体征、工作和生活能力评分均降低,治疗组评分明显低于对照组,P <0.01。结论:痛点注射所用药物腺苷钴胺可调节神经功能,修复受损神经;盐酸利多卡具有局部麻醉作用且有利于炎性介质吸收;鹿瓜多肽具有止痛抗炎消肿作用,可减少炎性渗出,促进局部血运障碍的恢复,还能抑制前列腺素的释放。针刀能疏通经络,调整颈部肌力平衡,促进颈椎力学平衡,改善微循环障碍,有利于血液循环,转运炎性物质,从而止痛。针刀联合痛点注射治疗神经根型颈椎病有良好的临床效果,两者有机结合,相互补充,能快速有效缓解颈部疼痛,改善神经功能,促进受损神经修复,且能解除颈部软组织对神经根的机械性压迫,恢复颈椎动态平衡,其疗效肯定,值得临床推广。

关键词：针刀痛点注射神经根型颈椎病

An Important Ornithischian Tracksite in the Early Jurassic of the Shenmu Region,Shaanxi,China

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 1-10页

作者： LI Jianjun Martin G.LOCKLEY ZHANG Yuguang HU Songmei MATSUKAWA Masaki bai zhiqiang Beijing Museum of Natural History Beijing 100050China Dinosaur Tracks Museum CB 172University of Colorado at DenverColorado80217-3364 USA Archaeological Research Institute of Shaanxi Province Xi'anShaanxi 710054China Department of Environmental Sciences Tokyo Gakugei UniversityKoganeiTokyo 184-8501Japan School of Earth and Space Sciences Peking UniversityBeo'ing 100871China

A large track site with multiple, well-preserved trackways of an Early Jurassic quadrupedal ornithischian dinosaur is the first report of Moyenisauripus-like trackways from Asia, herein named Shenmuichnus youngteilhardorum. The tracks occur in a clastic fluvial sequence in the Fuxian Formation in Shenmu County, Shaanxi Province, which is in the same general region as the discovery site of Sinoichnites, the first dinosaur track reported from China. Based on size and morphology, it is likely that Sinoichnites, which is now lost, also represents an ornithischian. The Shenmuichnus youngteilhardorum trackways show two modes of preservation： the first representing deeper tracks, with sediment rims, results in Deltapodus-like tracks, with indistinct pes digit traces and sub-circular manus traces, the second produces Moyenosauripus-like tracks, with clear tridactyl and pentadactyl digit traces in the pes and manus respectively. Thus the Shenmu trackways play a key role in resolving globally significant ichnotaxonomic problems surrounding the nomenclature of Sinoichnites, Moyenosauripus, Deltapodus and other named （Ravatichnus） and unnamed trackways from Asia, Africa and Europe. In addition they shed important light on the paleogeographical and paleoecological distribution of quadrupedal ornithischians in the Early Mesozoic. The track site has been the focus of a major excavation to transfer the trackways from their original remote location to the new Shenmu Museum, in Shenmu City. Other tracksites in the area which reveal Anomoepus, Grallator and the Deltapodus morphotype, together with Shenmuichnus and plant fossil evidence, suggest an Early Jurassic age for the tracksite.

关键词： dinosaur tracks Early Jurasic Shenmu Shaanxi