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可控构建Co_(3)S_(4)@CoMoS核@壳材料用于氢溢流促进的高效加氢脱硫
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作者 鲍文静 冯超 +9 位作者 马书妍 闫登伟 张聪 岳长乐 王崇泽 郭海玲 王继乾 孙道峰 柳云骐 卢玉坤 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期154-170,共17页
过去几十年,通过催化加氢脱硫(HDS)实现超清洁油品的生产一直是石油炼制领域的研究重点.然而,常规的HDS催化剂因金属负载量较低及金属与载体之间的强相互作用,导致其对4,6-二甲基二苯并噻吩(4,6-DMDBT)类大分子的脱除效率较低.这类大分... 过去几十年,通过催化加氢脱硫(HDS)实现超清洁油品的生产一直是石油炼制领域的研究重点.然而,常规的HDS催化剂因金属负载量较低及金属与载体之间的强相互作用,导致其对4,6-二甲基二苯并噻吩(4,6-DMDBT)类大分子的脱除效率较低.这类大分子反应物由于具有较大的空间位阻,使得其在催化剂表面活性位点上的吸附和反应更为困难,往往通过氢化反应进行脱硫反应.因此,为实现有效的脱硫反应,必须发展能高效解离和活化氢物种的催化剂.此外,通过氢化反应高效地脱除4,6-DMDBT通常需要在高温高压等苛刻条件下进行,这要求催化剂具备更高的活性、选择性和稳定性.为解决上述问题,本文通过奥斯瓦尔德熟化法制备了一种由多孔CoMoS外壳和Co_(3)S_(4)内核构成的Co_(3)S_(4)@CoMoS核@壳材料,并用于4,6-DMDBT类大分子的脱除.同时,通过原位表征和理论计算研究了该催化材料在HDS反应中的构效关系.SEM结果显示,制得的Co_(3)S_(4)@CoMoS空心球外表面粗糙,由许多小纳米颗粒组成.TEM图像直观地显示了Co_(3)S_(4)@CoMoS催化剂的结构,其外壳和间隙厚度分别为80和100 nm,高度多孔的球体使核@壳材料能够提供较短的氢溢流距离,从而构建了一种高效的HDS纳米反应器.EDX结果显示Co,Mo和S元素在Co_(3)S_(4)@CoMoS催化剂上均匀分布.其中,Mo金属仅存在于纳米球的外壳上;除外层的CoMoS相外,Co元素还形成了一个由Co-S物种组成的独立核心.结合XRD结果可以确定,该催化剂是由Co促进的MoS_(2)外壳和Co_(3)S_(4)内核组成的Co_(3)S_(4)@CoMoS核@壳材料.电镜图像和氮气吸脱附等结果表明,Co_(3)S_(4)@CoMoS纳米球的外壳由(Co)MoS_(2)纳米片交错卷曲组装而成,壳层含有丰富的活性位点和发达的孔道结构,为反应物提供了充足的吸附位点.Co金属的掺杂增加了MoS_(2)晶体的无序度,使得MoS_(2)纳米片上形成了大量的不饱和硫空位.钴原子锚定在MoS_(2)边缘还可以抑制MoS_(2)纳米片的团聚,使得Co_(3)S_(4)@CoMoS催化剂上的层状MoS_(2)长度较短且堆叠层数较低,有利于活性位点的充分暴露.H_(2)-程序升温脱附和WO_(3)变色实验结果证实了Co_(3)S_(4)@CoMoS结构中的氢溢流效应.HDS实验结果表明,仅使用30 mg Co_(3)S_(4)@CoMoS催化剂就能够实现99.2%的二苯并噻吩转化率和94.9%的4,6-DMDBT转化率.推测在HDS反应中,含硫大分子锚定在CoMoS外壳的硫空位上,而内核Co_(3)S_(4)相能够引发氢溢流效应,并将活性氢物种传递给CoMoS相,用于吸附和脱除含硫反应物,从而在HDS反应中使CoMoS和Co_(3)S_(4)两相起到协同作用,进而实现针对4,6-DMDBT类大分子的深度加氢脱硫.同时,反应过程中小分子H_(2)则可以自由地通过壳体扩散到内核的Co_(3)S_(4)相上,被解离成溢流氢物种后又传递给外层壳体,使得硫空位在HDS中不断地形成和再生.此外,核@壳球体内部连续的介孔通道缩短了溢流氢物种的迁移距离,提高了活性物种的利用率.致密的壳体使催化剂在多次循环反应中保留了核@壳结构,提高了催化剂的使用寿命.理论计算结果表明,CoMoS相和Co_(3)S_(4)相间的强电荷转移增加了CoMoS相中硫原子的电子云密度,有利于反应物在活性物种上的吸附.此外,得益于Co_(3)S_(4)相的氢溢流效应,在CoMoS/Co_(3)S_(4)双相结构上的氢解离能远低于单相结构,这使得H2分子能够在核@壳催化剂上被快速活化,以促进反应物分子的下一步脱硫进程.综上所述,本文制备的多组分Co_(3)S_(4)@CoMoS核@壳催化剂表现出较好的加氢脱硫性能.文章还提出了活性相结构与催化活性及反应路径选择性之间的作用机制,为进一步开发高效非负载加氢脱硫催化剂提供了新思路. 展开更多
关键词 加氢脱硫 氢溢流效应 核@壳结构 CoMoS活性相 双活性相协同
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Numerical Simulation of Surrounding Rock Deformation and Grouting Reinforcement of Cross-Fault Tunnel under Different Excavation Methods
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作者 Duan Zhu Zhende Zhu +2 位作者 cong zhang LunDai Baotian Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2445-2470,共26页
Tunnel construction is susceptible to accidents such as loosening, deformation, collapse, and water inrush, especiallyunder complex geological conditions like dense fault areas. These accidents can cause instability a... Tunnel construction is susceptible to accidents such as loosening, deformation, collapse, and water inrush, especiallyunder complex geological conditions like dense fault areas. These accidents can cause instability and damageto the tunnel. As a result, it is essential to conduct research on tunnel construction and grouting reinforcementtechnology in fault fracture zones to address these issues and ensure the safety of tunnel excavation projects. Thisstudy utilized the Xianglushan cross-fault tunnel to conduct a comprehensive analysis on the construction, support,and reinforcement of a tunnel crossing a fault fracture zone using the three-dimensional finite element numericalmethod. The study yielded the following research conclusions: The excavation conditions of the cross-fault tunnelarray were analyzed to determine the optimal construction method for excavation while controlling deformationand stress in the surrounding rock. The middle partition method (CD method) was found to be the most suitable.Additionally, the effects of advanced reinforcement grouting on the cross-fault fracture zone tunnel were studied,and the optimal combination of grouting reinforcement range (140°) and grouting thickness (1m) was determined.The stress and deformation data obtained fromon-site monitoring of the surrounding rock was slightly lower thanthe numerical simulation results. However, the change trend of both sets of data was found to be consistent. Theseresearch findings provide technical analysis and data support for the construction and design of cross-fault tunnels. 展开更多
关键词 Cross-fault tunnel finite element analysis excavation methods surrounding rock deformation grouting reinforcement
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The electrical design of a membrane antenna for a lunar-based low-frequency radio telescope
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作者 Suonanben Fengquan Wu +15 位作者 Kai He Shijie Sun Wei Zhou Minquan Zhou cong zhang Jiaqin Xu Qisen Yan Shenzhe Xu Jiacong Zhu Zhao Wang Ke zhang Haitao Miao Jixia Li Yougang Wang Tianlu Chen Xuelei Chen 《Astronomical Techniques and Instruments》 CSCD 2024年第4期227-238,共12页
Detecting primordial fluctuations from the cosmic dark ages requires extremely large low-frequency radio telescope arrays deployed on the far side of the Moon.The antenna of such an array must be lightweight,easily st... Detecting primordial fluctuations from the cosmic dark ages requires extremely large low-frequency radio telescope arrays deployed on the far side of the Moon.The antenna of such an array must be lightweight,easily storable and transportable,deployable on a large scale,durable,and capable of good electrical performance.A membrane antenna is an excellent candidate to meet these criteria.We study the design of a low-frequency membrane antenna for a lunar-based low-frequency(<30 MHz)radio telescope constructed from polyimide film widely used in aerospace applications,owing to its excellent dielectric properties and high stability as a substrate material.We first design and optimize an antenna in free space through dipole deformation and coupling principles,then simulate an antenna on the lunar surface with a simple lunar soil model,yielding an efficiency greater than 90%in the range of 12-19 MHz and greater than 10%in the range of 5-35 MHz.The antenna inherits the omni-directional radiation pattern of a simple dipole antenna in the 5-30 MHz frequency band,giving a large field of view and allowing detection of the 21 cm global signal when used alone.A demonstration prototype is constructed,and its measured electrical property is found to be consistent with simulated results using|S11|measurements.This membrane antenna can potentially fulfill the requirements of a lunar low-frequency array,establishing a solid technical foundation for future large-scale arrays for exploring the cosmic dark ages. 展开更多
关键词 Membrane antenna Lunar-based radio array Cosmic dark ages
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1例误诊为原发性精神病的额颞叶痴呆病例讨论
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作者 黄志宏 张帆 +2 位作者 郭俊清 张聪 曾国勇 《阿尔茨海默病及相关病杂志》 2024年第3期210-213,217,共5页
目的:报道1例早期误诊为原发性精神病的额颞叶痴呆患者诊疗过程并进行讨论分析。方法:对1例行为变异型额颞叶痴呆患者的临床和神经影像学表现进行分析。结果:本病例为中年女性,首发表现为精神异常,在外院先后诊断为抑郁症、精神分裂症,... 目的:报道1例早期误诊为原发性精神病的额颞叶痴呆患者诊疗过程并进行讨论分析。方法:对1例行为变异型额颞叶痴呆患者的临床和神经影像学表现进行分析。结果:本病例为中年女性,首发表现为精神异常,在外院先后诊断为抑郁症、精神分裂症,予药物治疗后效果不佳,行头颅MRI示双侧额颞叶萎缩,左侧明显。头颅18F-FDG PET示:双侧侧额叶、颞叶外侧代谢减低。FTD相关基因检测发现该患者存在易感基因突变。结论:这是1例典型的bvFTD病例,早期被误诊为原发性精神病,这提示在精神异常的诊断过程中,需与bvFTD鉴别诊断。 展开更多
关键词 额颞叶痴呆 原发性精神病 误诊
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Zeolitic imidazolate framework-8 modified poly(vinylidene fluoride-cohexafluoropropylene)/polyacrylonitrile composite separators for Li-ion batteries 被引量:2
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作者 Yanhuai Ding cong zhang +1 位作者 Hao Zheng Yi Han 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第10期291-296,共6页
As one of the most stable metal-organtic framework(MOF),zeolitic imidazolate framework-8(ZIF-8)has been widely studied for applications in the field of energy storage,catalysis,and environment protection.In this paper... As one of the most stable metal-organtic framework(MOF),zeolitic imidazolate framework-8(ZIF-8)has been widely studied for applications in the field of energy storage,catalysis,and environment protection.In this paper,ZIF-8 was employed to enhance the electrochemical properties and thermal stability of the electrospun poly(vinylidene fluoride-co-hexafluoropropylene)/polyacrylonitrile(PVDF-HFP/PAN)composite separator.The results indicate that the test cells assembled with the composite separators show improved rate capability,high discharge capacity,and stable cycling performances.The addition of ZIF-8 can improve the affinity of PVDF-HFP/PAN toward liquid electrolytes,and further enhance the ionic conductivity of the composite separators.In addition,the thermal stability of the PVDF-HFP/PAN separator has been improved by ZIF-8 nanoparticles.This work can provide insight into the application of MOF materials in Li-ion batteries. 展开更多
关键词 NANOTECHNOLOGY ZIF-8 PVDF-HFP/PAN Composites Electrolytes
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类器官模型在肿瘤精准诊疗中的应用 被引量:2
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作者 王海霞 张聪 邹冬玲 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第6期291-295,共5页
过去10年中,三维类器官技术得到了快速发展,目前已经可以从正常组织和恶性肿瘤组织中高效地建立类器官。患者来源的肿瘤类器官(patient-derived tumor-organoids,PDOs)可以很好地保留亲本肿瘤的生理病理学及遗传学特征,最大限度地保持... 过去10年中,三维类器官技术得到了快速发展,目前已经可以从正常组织和恶性肿瘤组织中高效地建立类器官。患者来源的肿瘤类器官(patient-derived tumor-organoids,PDOs)可以很好地保留亲本肿瘤的生理病理学及遗传学特征,最大限度地保持肿瘤异质性。PDOs已被用于阐明关键的科学问题,包括感染病原体或遗传/表观遗传学改变与肿瘤发生之间的关系、耐药机制、预测患者对选定治疗方案的反应。随着类器官与肿瘤微环境的细胞成分共培养系统的建立,该技术现在也被应用于快速发展的免疫肿瘤学领域。本文综述了类器官技术在肿瘤精准医学领域的研究现状、应用及面临的挑战。 展开更多
关键词 类器官 肿瘤 精准诊疗
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SPP-extractor:Automatic phenotype extraction for densely grown soybean plants
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作者 Wan Zhou Yijie Chen +6 位作者 Weihao Li cong zhang Yajun Xiong Wei Zhan Lan Huang Jun Wang Lijuan Qiu 《The Crop Journal》 SCIE CSCD 2023年第5期1569-1578,共10页
Automatic collecting of phenotypic information from plants has become a trend in breeding and smart agriculture.Targeting mature soybean plants at the harvesting stage,which are dense and overlapping,we have proposed ... Automatic collecting of phenotypic information from plants has become a trend in breeding and smart agriculture.Targeting mature soybean plants at the harvesting stage,which are dense and overlapping,we have proposed the SPP-extractor(soybean plant phenotype extractor)algorithm to acquire phenotypic traits.First,to address the mutual occultation of pods,we augmented the standard YOLOv5s model for target detection with an additional attention mechanism.The resulting model could accurately identify pods and stems and could count the entire pod set of a plant in a single scan.Second,considering that mature branches are usually bent and covered with pods,we designed a branch recognition and measurement module combining image processing,target detection,semantic segmentation,and heuristic search.Experimental results on real plants showed that SPP-extractor achieved respective R^(2) scores of 0.93–0.99 for four phenotypic traits,based on regression on manual measurements. 展开更多
关键词 Soybean phenotype Branch length Computer vision A*algorithm Phenotype acquisition
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Stabilizing Buried Interface via Synergistic Effect of Fluorine and Sulfonyl Functional Groups Toward Efficient and Stable Perovskite Solar Cells
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作者 Cheng Gong cong zhang +4 位作者 Qixin Zhuang Haiyun Li Hua Yang Jiangzhao Chen Zhigang Zang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第2期32-45,共14页
The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further en... The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further enhancement of the photovoltaic performance of the devices using sequential deposition.Herein,a buried interface stabilization strategy that relies on the synergy of fluorine(F)and sulfonyl(S=O)functional groups is proposed.A series of potassium salts containing halide and non-halogen anions are employed to modify SnO_(2)/perovskite buried interface.Multiple chemical bonds including hydrogen bond,coordination bond and ionic bond are realized,which strengthens interfacial contact and defect passivation effect.The chemical interaction between modification molecules and perovskite along with SnO_(2) heightens incessantly as the number of S=O and F augments.The chemical interaction strength between modifiers and perovskite as well as SnO_(2) gradually increases with the increase in the number of S=O and F.The defect passivation effect is positively correlated with the chemical interaction strength.The crystallization kinetics is regulated through the compromise between chemical interaction strength and wettability of substrates.Compared with Cl−,all non-halogen anions perform better in crystallization optimization,energy band regulation and defect passivation.The device with potassium bis(fluorosulfonyl)imide achieves a tempting efficiency of 24.17%. 展开更多
关键词 Perovskite solar cells Buried interface Multiple chemical bonds Synergistic effect of functional groups Defect passivation
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Peripheral actions and direct central-local communications of melanocortin 4 receptor signaling
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作者 Lei Li Jinye Liang +2 位作者 cong zhang Tiemin Liu Chao zhang 《Journal of Sport and Health Science》 SCIE CSCD 2023年第1期45-51,共7页
Melanocortin 4 receptor(MC4R),the most important monogenetic cause of human metabolic disorders,has been of great interest to many researchers in the field of energy homeostasis and public health.Because MC4R is a vit... Melanocortin 4 receptor(MC4R),the most important monogenetic cause of human metabolic disorders,has been of great interest to many researchers in the field of energy homeostasis and public health.Because MC4R is a vital pharmaceutical target for maintaining controllable appetite and body weight for professional athletes,previous studies have mainly focused on the central,rather than the peripheral,roles of MC4R.Thus,the local expression of MC4R and its behavioral regulation remain unclear.In an attempt to shed light on different directions for future studies of MC4R signaling,we review a series of recent and important studies exploring the peripheral functions of MC4R and the direct physiological interaction between peripheral organs and central MC4R neurons in this article. 展开更多
关键词 Body weight Energy homeostasis GPCR Melanocortin-4 receptor
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Temperature-Triggered Hardware Trojan Based Algebraic Fault Analysis of SKINNY-64-64 Lightweight Block Cipher
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作者 Lei Zhu Jinyue Gong +1 位作者 Liang Dong cong zhang 《Computers, Materials & Continua》 SCIE EI 2023年第6期5521-5537,共17页
SKINNY-64-64 is a lightweight block cipher with a 64-bit block length and key length,and it is mainly used on the Internet of Things(IoT).Currently,faults can be injected into cryptographic devices by attackers in a v... SKINNY-64-64 is a lightweight block cipher with a 64-bit block length and key length,and it is mainly used on the Internet of Things(IoT).Currently,faults can be injected into cryptographic devices by attackers in a variety of ways,but it is still difficult to achieve a precisely located fault attacks at a low cost,whereas a Hardware Trojan(HT)can realize this.Temperature,as a physical quantity incidental to the operation of a cryptographic device,is easily overlooked.In this paper,a temperature-triggered HT(THT)is designed,which,when activated,causes a specific bit of the intermediate state of the SKINNY-64-64 to be flipped.Further,in this paper,a THT-based algebraic fault analysis(THT-AFA)method is proposed.To demonstrate the effectiveness of the method,experiments on algebraic fault analysis(AFA)and THT-AFA have been carried out on SKINNY-64-64.In the THT-AFA for SKINNY-64-64,it is only required to activate the THT 3 times to obtain the master key with a 100%success rate,and the average time for the attack is 64.57 s.However,when performing AFA on this cipher,we provide a relation-ship between the number of different faults and the residual entropy of the key.In comparison,our proposed THT-AFA method has better performance in terms of attack efficiency.To the best of our knowledge,this is the first HT attack on SKINNY-64-64. 展开更多
关键词 SKINNY-64-64 lightweight block cipher algebraic fault analysis Hardware Trojan residual entropy
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Neural Machine Translation by Fusing Key Information of Text
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作者 Shijie Hu Xiaoyu Li +8 位作者 Jiayu Bai Hang Lei Weizhong Qian Sunqiang Hu cong zhang Akpatsa Samuel Kofi Qian Qiu Yong Zhou Shan Yang 《Computers, Materials & Continua》 SCIE EI 2023年第2期2803-2815,共13页
When the Transformer proposed by Google in 2017,it was first used for machine translation tasks and achieved the state of the art at that time.Although the current neural machine translation model can generate high qu... When the Transformer proposed by Google in 2017,it was first used for machine translation tasks and achieved the state of the art at that time.Although the current neural machine translation model can generate high quality translation results,there are still mistranslations and omissions in the translation of key information of long sentences.On the other hand,the most important part in traditional translation tasks is the translation of key information.In the translation results,as long as the key information is translated accurately and completely,even if other parts of the results are translated incorrect,the final translation results’quality can still be guaranteed.In order to solve the problem of mistranslation and missed translation effectively,and improve the accuracy and completeness of long sentence translation in machine translation,this paper proposes a key information fused neural machine translation model based on Transformer.The model proposed in this paper extracts the keywords of the source language text separately as the input of the encoder.After the same encoding as the source language text,it is fused with the output of the source language text encoded by the encoder,then the key information is processed and input into the decoder.With incorporating keyword information from the source language sentence,the model’s performance in the task of translating long sentences is very reliable.In order to verify the effectiveness of the method of fusion of key information proposed in this paper,a series of experiments were carried out on the verification set.The experimental results show that the Bilingual Evaluation Understudy(BLEU)score of the model proposed in this paper on theWorkshop on Machine Translation(WMT)2017 test dataset is higher than the BLEU score of Transformer proposed by Google on the WMT2017 test dataset.The experimental results show the advantages of the model proposed in this paper. 展开更多
关键词 Key information TRANSFORMER FUSION neural machine translation
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Treatment of talipes equinovarus after triceps surae intramuscular hemangioma surgery by Ilizarov technology in adults:A case report
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作者 zhang-Xin Chen Meng-Yuan Wang +2 位作者 cong zhang Zhen-Qi Ding Wei Chen 《World Journal of Clinical Cases》 SCIE 2023年第12期2803-2810,共8页
BACKGROUND Postoperative complications of triceps surae intramuscular hemangioma surgery with talipes equinovarus have rarely been described,and the evidence for treatment is limited.The purpose of this case study was... BACKGROUND Postoperative complications of triceps surae intramuscular hemangioma surgery with talipes equinovarus have rarely been described,and the evidence for treatment is limited.The purpose of this case study was to report the new application of the Ilizarov technique,which successfully treated talipes equinovarus in adults after triceps surae intramuscular hemangioma.CASE SUMMARY A 29-year-old woman treated with the Ilizarov technique for talipes equinovarus in the right leg after triceps surae intramuscular hemangioma surgery.The equinus deformity was roughly corrected after 2 years of follow-up,without significant secondary sequelae.CONCLUSION Talipes equinovarus caused by postoperative sequelae of intramuscular hemangioma was successfully corrected by the Ilizarov technique.The Ilizarov technique may be used for treating talipes equinovarus caused by various causes. 展开更多
关键词 Triceps surae intramuscular hemangioma Ilizarov technique Talipes equinovarus TREATMENT Case report
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Enhancing the Adversarial Transferability with Channel Decomposition
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作者 Bin Lin Fei Gao +7 位作者 Wenli Zeng Jixin Chen cong zhang Qinsheng Zhu Yong Zhou Desheng Zheng Qian Qiu Shan Yang 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3075-3085,共11页
The current adversarial attacks against deep learning models have achieved incredible success in the white-box scenario.However,they often exhibit weak transferability in the black-box scenario,especially when attacki... The current adversarial attacks against deep learning models have achieved incredible success in the white-box scenario.However,they often exhibit weak transferability in the black-box scenario,especially when attacking those with defense mechanisms.In this work,we propose a new transfer-based blackbox attack called the channel decomposition attack method(CDAM).It can attack multiple black-box models by enhancing the transferability of the adversarial examples.On the one hand,it tunes the gradient and stabilizes the update direction by decomposing the channels of the input example and calculating the aggregate gradient.On the other hand,it helps to escape from local optima by initializing the data point with random noise.Besides,it could combine with other transfer-based attacks flexibly.Extensive experiments on the standard ImageNet dataset show that our method could significantly improve the transferability of adversarial attacks.Compared with the state-of-the-art method,our approach improves the average success rate from 88.2%to 96.6%when attacking three adversarially trained black-box models,demonstrating the remaining shortcomings of existing deep learning models. 展开更多
关键词 Adversarial attack transferability black-box models deep learning
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Rotationplasty type BIIIb as an effective alternative to limb salvage procedure in adults:Two case reports
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作者 zhang-Xin Chen Xiao-Wei Guo +4 位作者 Hai-Sen Hong cong zhang Wei Xie Mo Sha Zhen-Qi Ding 《World Journal of Clinical Cases》 SCIE 2023年第28期6877-6888,共12页
BACKGROUND Rotationplasty is often performed for malignant tumors,but type BIIIb rotationplasty is rarely reported,and there needs to be more evidence of the procedure and treatment.The purpose of this case study was ... BACKGROUND Rotationplasty is often performed for malignant tumors,but type BIIIb rotationplasty is rarely reported,and there needs to be more evidence of the procedure and treatment.The purpose of this case study was to report a new direction in the use of type BIIIb rotationplasty in treating patients with limb salvage and longterm non-healing infections.CASE SUMMARY Case 1:A 47-year-old man underwent radiotherapy for hemangioendothelioma in his left thigh,resulting in a femoral fracture.Despite the use of plates,intramedullary nailing,and external fixators,the femoral bone failed to unite due to infectious nonunion.Multiple operations were unable to control the infection,leaving the patient immobile.We performed a modified tibia-pelvic-constrained hip rotationplasty,utilizing a constrained prosthetic hip between the tibia and pelvis following a femur resection.Two years post-surgery,the patient was able to walk with the prosthetic device without any signs of recurring infection.The corresponding functional scores were 72 points for the Musculoskeletal Tumor Society(MSTS),53 for the Functional Mobility Assessment(FMA),93 for the Toronto Extremity Salvage Score(TESS),and 56 for the MOS 36-item short form health survey(SF-36).Case 2:A 59-year-old woman presented with liposarcoma in her left thigh.Magnetic resonance imaging revealed tumors in the medial,anterior,and posterior femur muscles,encircling the femoral vessels and nerves.Fortunately,there were no symptoms of sciatic dysfunction,and the tumor had not invaded the sciatic nucleus.After one year of follow-up,the patient expressed satisfaction with limb preservation post-type BIIIb rotationplasty.The corresponding functional scores were 63 points for the MSTS,47 for the FMA,88 for the TESS,and 52 for the SF-36.CONCLUSION Our study suggests that type BIIIb rotationplasty may be an alternative to amputation in patients with incurable infections.For malignant tumors of the lower extremities without invasion of the sciatic nerve,type BIIIb rotationplasty remains an excellent alternative to amputation.This surgical method may prevent amputation,improve functional outcomes,and facilitate biological reconstruction. 展开更多
关键词 Salvage procedure Type BIIIb rotationplasty HEMANGIOENDOTHELIOMA Incurable infections LIPOSARCOMA Case report
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玻璃体切割联合内界膜剥除术治疗顽固性糖尿病黄斑水肿 被引量:4
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作者 张聪 许贺 徐丽 《国际眼科杂志》 CAS 北大核心 2020年第12期2159-2162,共4页
目的:观察玻璃体切割术(PPV)联合内界膜(ILM)剥除术治疗顽固性糖尿病黄斑水肿的临床疗效。方法:回顾性分析顽固性糖尿病黄斑水肿并行PPV联合ILM剥除术患者56例56眼,根据有无后极部玻璃体后脱离分为A组(无玻璃体后脱离,35例35眼)和B组(... 目的:观察玻璃体切割术(PPV)联合内界膜(ILM)剥除术治疗顽固性糖尿病黄斑水肿的临床疗效。方法:回顾性分析顽固性糖尿病黄斑水肿并行PPV联合ILM剥除术患者56例56眼,根据有无后极部玻璃体后脱离分为A组(无玻璃体后脱离,35例35眼)和B组(有玻璃体后脱离,21例21眼)。对比分析手术前及手术后1、3、6mo时患眼最佳矫正视力(BCVA)、黄斑中心视网膜厚度(CMT)变化情况。结果:A组手术后1、3、6mo平均CMT和BCVA与手术前比较均有差异(P<0.05)。B组手术后1、3、6mo平均BCVA与手术前比较均无差异(P>0.05);手术后1mo平均CMT与手术前比较有差异(P<0.05),术后3、6mo平均CMT与手术前比较均无差异(P>0.05)。术后1、3、6mo,两组CMT、BCVA比较均有差异(P<0.05)。结论:PPV联合ILM剥除术能有效治疗无玻璃体后脱离的顽固性糖尿病黄斑水肿,提高患者视力;但当患者玻璃体已经后脱离且没有牵拉时,PPV联合ILM剥除术治疗效果不佳。 展开更多
关键词 玻璃体切割 内界膜剥除 糖尿病黄斑水肿 玻璃体后脱离
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Ji Desheng Snake Pills Combined with Hypertonic Glucose External Application in the Treatment of Stage III and IV Pressure Injuries
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作者 Rongting Liu cong zhang +3 位作者 Jing Zeng Xue Wu Shihong Deng Jing Chen 《Yangtze Medicine》 2021年第2期117-124,共8页
<strong>Background:</strong> As a common surgical disease, pressure injury has become a long-standing problem in clinical treatment and nursing process. This research was conducted to explore the feasibili... <strong>Background:</strong> As a common surgical disease, pressure injury has become a long-standing problem in clinical treatment and nursing process. This research was conducted to explore the feasibility of Ji Desheng Snake Pills combined with hypertonic glucose external application in the treatment of stage III and IV pressure injuries. <strong>Methods:</strong> Patients with stage III and IV pressure injuries, who received treatment in our hospital between December 2018 and December 2019 were selected and divided into experimental group, conventional treatment group, and control group, 30 cases for each. The three groups received Ji Desheng Snake Pills combined with hypertonic glucose external application, moist dressing external application and surgical dressing change, respectively. The safety, therapeutic effect and cost benefit of the three treatment methods were compared. <strong>Results:</strong> There were no adverse reactions in the three groups of patients. The PUSH scores of the experimental group and the conventional treatment group were significantly lower than that of the control group on the 14<sup>th</sup>, 21<sup>th</sup>, and 28<sup>th</sup> days, and the result was statistically significant (p < 0.05), while there was no significant difference between the experimental group and the conventional treatment group (p > 0.05). The wound healing rates of the experimental group (70.14 ± 8.27%) and the conventional treatment group (73.99 ± 7.15%) were significantly higher than that of the control group (43.25 ± 8.53%) on the 28<sup>th</sup> day, with statistical significance (p < 0.05);there was no significant difference between the experimental group and the conventional treatment group (p > 0.05). The total treatment costs of the three groups were 569.73 ± 78.12 yuan, 1043.40 ± 135.31 yuan, and 186.47 ± 30.29 yuan. The cost of the conventional treatment group was the highest, followed by the experimental group, and the control group was the lowest. The result was statistically significant (p < 0.05). <strong>Conclusion:</strong> In the treatment of stage III and IV pressure injuries, there was no significant difference in the safety and therapeutic effect between the experimental group (Ji Desheng Snake Pills combined with hypertonic glucose external application) and the conventional treatment group (moist dressing external application), but the experimental group had better cost benefit. 展开更多
关键词 Ji Desheng Snake Pills Hypertonic Glucose Pressure Ulcer Pressure Ulcer Scale for Healing Tool
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Rosmarinic acid elicits neuroprotection in ischemic stroke via Nrf2 and heme oxygenase 1 signaling 被引量:10
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作者 Hai-Ying Cui Xiang-Jian zhang +4 位作者 Yi Yang cong zhang Chun-Hua Zhu Jiang-Yong Miao Rong Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2119-2128,共10页
Rosmarinic acid(RA) can elicit a neuroprotective effect against ischemic stroke, but the precise molecular mechanism remains poorly understood. In this study, an experimental ischemic stroke model was established in... Rosmarinic acid(RA) can elicit a neuroprotective effect against ischemic stroke, but the precise molecular mechanism remains poorly understood. In this study, an experimental ischemic stroke model was established in CD-1 mice(Beijing Vital River Laboratory Animal Technology, Beijing, China) by occluding the right middle cerebral artery for 1 hour and allowing reperfusion for 24 hours. After intraperitoneally injecting model mice with 10, 20, or 40 mg/kg RA, functional neurological deficits were evaluated using modified Longa scores. Subsequently, cerebral infarct volume was measured using TTC staining and ischemic brain tissue was examined for cell apoptosis with TUNEL staining. Superoxide dismutase activity and malondialdehyde levels were measured by spectrophometry. Expression of heme oxygenase-1(HO-1), nuclear factor erythroid 2-related factor 2(Nrf2), Bcl-2, Bax, Akt, and phospho-Ser473 Akt proteins in ischemic brain tissue was detected by western blot, while mRNA levels of Nrf2, HO-1, Bcl-2, and Bax were analyzed using real time quantitative PCR. In addition, HO-1 enzyme activity was measured spectrophotometrically. RA(20 and 40 mg/kg) greatly improved neurological function, reduced infarct volume, decreased cell apoptosis, upregulated Bcl-2 protein and mRNA expression, downregulated Bax protein and mRNA expression, increased HO-1 and Nrf2 protein and mRNA expression, increased superoxide dismutase activity, and decreased malondialdehyde levels in ischemic brain tissue of model mice. However, intraperitoneal injection of a HO-1 inhibitor(10 mg/kg zinc protoporphyrin IX) reversed the neuroprotective effects of RA on HO-1 enzyme activity and Bcl-2 and Bax protein expression. The PI3 K/Akt signaling pathway inhibitor LY294002(10 mM) inhibited Akt phosphorylation, as well as Nrf2 and HO-1 expression. Our findings suggest that RA has anti-oxidative and anti-apoptotic properties that protect against ischemic stroke by a mechanism involving upregulation of Nrf2 and HO-1 expression via the PI3 K/Akt signaling pathway. 展开更多
关键词 cerebral ischemia/reperfusion rosmarinic acid cellular apoptosis oxidative injury NEUROPROTECTION Bcl-2 Bax NRF2 heme oxygenase 1 PI3K/Akt signal pathway neural regeneration
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Machine-learning-assisted prediction of the mechanical properties of Cu–Al alloy 被引量:11
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作者 Zheng-hua Deng Hai-qing Yin +7 位作者 Xue Jiang cong zhang Guo-fei zhang Bin Xu Guo-qiang Yang Tong zhang Mao Wu Xuan-hui Qu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第3期362-373,共12页
The machine-learning approach was investigated to predict the mechanical properties of Cu–Al alloys manufactured using the powder metallurgy technique to increase the rate of fabrication and characterization of new m... The machine-learning approach was investigated to predict the mechanical properties of Cu–Al alloys manufactured using the powder metallurgy technique to increase the rate of fabrication and characterization of new materials and provide physical insights into their properties.Six algorithms were used to construct the prediction models, with chemical composition and porosity of the compacts chosen as the descriptors.The results show that the sequential minimal optimization algorithm for support vector regression with a puk kernel(SMOreg/puk) model demonstrated the best prediction ability. Specifically, its predictions exhibited the highest correlation coefficient and lowest error among the predictions of the six models. The SMOreg/puk model was subsequently applied to predict the tensile strength and hardness of Cu–Al alloys and provide guidance for composition design to achieve the expected values. With the guidance of the SMOreg/puk model, Cu–12Al–6Ni alloy with a tensile strength(390 MPa) and hardness(HB 139) that reached the expected values was developed. 展开更多
关键词 powder metallurgy tensile strength HARDNESS machine learning Cu–Al alloy SMOreg/puk
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Four new observational H(z) data from luminous red galaxies in the Sloan Digital Sky Survey data release seven 被引量:8
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作者 cong zhang Han zhang +3 位作者 Shuo Yuan Siqi Liu Tong-Jie zhang Yan-Chun Sun 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第10期1221-1233,共13页
By adopting the differential age method, we select 17 832 luminous red galaxies from the Sloan Digital Sky Survey Data Release Seven covering redshift 0 〈 z 〈 0.4 to measure the Hubble parameter. Using the full spec... By adopting the differential age method, we select 17 832 luminous red galaxies from the Sloan Digital Sky Survey Data Release Seven covering redshift 0 〈 z 〈 0.4 to measure the Hubble parameter. Using the full spectrum fitting package UZySS, these spectra are reduced with single stellar population models and optimal age information from our selected sample is derived. With the decreasing age-redshift relation, four new observational H(z) data (OHD) points are obtained, which are H(z) = 69.0 ± 19.6 km s^-1 Mpc^-1 at z = 0.07, H(z) = 68.6± 26.2 km s^-1 Mpc^-1 at z = 0.12, H(z)=72.9 ± 29.6 km s^-1 Mpc^-1 at z = 0.2 and H(z)=88.8 ± 36.6 km s^-1 Mpc^-1 at z = 0.28, respectively. Combined with 21 other available OHD data points, the performance of the constraint on both flat and non-flat ACDM models is presented. 展开更多
关键词 COSMOLOGY cosmological parameters -- cosmology observations --galaxies evolution
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Electron-beam radiation effects on the structure and properties of polypropylene at low dose rates 被引量:5
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作者 Heng-Ti Wang Hai-Qing Jiang +4 位作者 Rong-Fang Shen Xiao-Jun Ding cong zhang Lin-Fan Li Jing-Ye Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第6期101-109,共9页
While the high-energy radiation effects on polypropylene, which are crucial for the cable industry for nuclear power plants, have been thoroughly studied, the property changes of PP at low-dose-rate electron-beam irra... While the high-energy radiation effects on polypropylene, which are crucial for the cable industry for nuclear power plants, have been thoroughly studied, the property changes of PP at low-dose-rate electron-beam irradiation are far from elucidated. Herein, the influence of electron-beam irradiation on the structure and properties of PP was examined. The static EB irradiation conditions were 1.2 MeV at a low dose rate of 20 kGy/h to achieve absorbed doses ranging from 45, to 60, 100, and 200 kGy.The molecular structure was first evaluated by measuring the carboxyl index and the relative radical concentrations via Fourier transform infrared spectroscopy and electron spin resonance, respectively. Mechanical, differential scanning colorimetric, and rheological tests were carried out to further investigate the changes in the properties(tensile, crystalizing, and viscoelastic properties) of irradiated PP, which showed good agreement with the structural analysis results. We found that radio-oxidative degradation(chain scission) was predominant, which can be due to the low dose rate facilitating oxygen diffusion into the PP matrix during electron-beam irradiation. 展开更多
关键词 性质变化 低剂量率 聚丙烯 电子 横梁 结构 放射 FOURIER
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