Development review and the prospect of oil shale in-situ catalysis conversion technology

As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.

Technical development of operational in-situ marine monitoring and research on its key generic technologies in China

In China,operational in-situ marine monitoring is the primary means of directly obtaining hydrological,meteorological,and oceanographic environmental parameters across sea areas,and it is essential for applications such as forecast of marine environment,prevention and mitigation of disaster,exploitation of marine resources,marine environmental protection,and management of transportation safety.In this paper,we summarise the composition,development courses,and present operational status of three systems of operational in-situ marine monitoring,namely coastal marine automated network station,ocean data buoy and voluntary observing ship measuring and reporting system.Additionally,we discuss the technical development in these in-situ systems and achievements in the key generic technologies along with future development trends.

Properties of n-Ge epilayer on Si substrate with in-situ doping technology

The properties of n-Ge epilayer deposited on Si substrate with in-situ doping technology in a cold-wall ultrahigh vacuum chemical vapor deposition（UHVCVD） system are investigated.The growth temperature of 500℃ is optimal for the n-Ge growth in our equipment with a phosphorus concentration of 1018cm-3.In the n-Ge epilayer,the depth profile of phosphorus concentration is box-shaped and the tensile strain of 0.12% confirmed by x-ray diffraction measurement is introduced which results in the red shift of the photoluminescence.The enhancements of photoluminescence intensity with the increase of the doping concentration are observed,which is consistent with the modeling of the spontaneous emission spectrum for direct transition of Ge.The results are of significance for guiding the growth of n-Ge epilayer with in-situ doping technology.

Innovation and development of the third-generation hybrid rice technology

The breeding and large-scale application of hybrid rice contribute significantly to the food supply worldwide.Currently,hybrid seed production uses cytoplasmic male sterile(CMS)lines or photoperiod/thermo-sensitive genic male sterile(PTGMS)lines as female parent.Despite huge successes,both systems have intrinsic problems.CMS systems are mainly restricted by the narrow restorer resources that make it difficult to breed superior hybrids,while PTGMS systems are limited by conditional sterility of the male sterile lines that makes the propagation of both PTGMS seeds and hybrid seeds vulnerable to unpredictable climate changes.Recessive nuclear male sterile(NMS)lines insensitive to environmental conditions are widely distributed and are ideal for hybrid rice breeding and production,but the lack of effective ways to propagate the pure NMS lines in a large scale renders it impossible to use them for hybrid rice production.The development of"the third-generation hybrid rice technology"enables efficient propagation of the pure NMS lines in commercial scale.This paper discusses the establishment of"the thirdgeneration hybrid rice technology"and further innovations.This new technology breaks the limitations of CMS and PTGMS systems and will bring a big leap forward in hybrid rice production.

光动力技术对副溶血性弧菌的灭活作用

该文探究了姜黄素介导的光动力技术(photodynamic technology,PDT)协同柠檬酸处理对副溶血性弧菌的灭活效果和机理。通过平板菌落计数法测定光动力技术对副溶血性弧菌的灭活效果、扫描电镜观察细菌形态变化,酶标仪检测PDT处理后菌体活性氧(reactive oxygen species,ROS)水平以及过氧化氢酶(catalase,CAT)、超氧化物歧化酶(superoxide dismutase,SOD)、腺苷三磷酸酶(adenosine triphosphatase,ATPase)、碱性磷酸酶(alkaline phosphatase,AKP)的活性变化,琼脂糖凝胶电泳分析基因损伤程度。结果表明,PDT杀菌效果随姜黄素浓度增加、光照时间延长和柠檬酸(0.5 mg/mL)的添加而显著增强(在最高浓度姜黄素条件下P<0.05)。当姜黄素浓度为2μmol/L,柠檬酸质量浓度为0.5 mg/mL,光照2 min后,PBS中的副溶血性弧菌菌落总数从7.43 lg CFU/mL降至0。光敏剂姜黄素被蓝光激活后通过电子转移和能量转移产生具有强氧化性的ROS,菌体内ROS水平不断升高,胞内抗氧化酶(CAT、SOD)活性下降,ATPase活性下降,上清液中AKP活性上升,细菌发生严重形变甚至趋向于扁平,DNA条带变暗甚至消失,最终导致细胞死亡。综上,姜黄素介导的PDT对副溶血性弧菌有较强的杀灭作用,添加柠檬酸显著加强杀菌效果,为PDT在水产食品安全防控领域的推广应用提供了参考。

光动力抗菌技术在鲜切菜加工除菌过程中的应用研究进展

微生物灭活作为鲜切菜加工过程中关键的步骤之一,关系着鲜切菜的保质期与食品安全问题。因此,研究和利用各种除菌技术以延长鲜切菜保鲜期、保证食品安全与质量十分重要。光动力抗菌技术(photodynamic antimicrobial technology,PDAT)是一种新兴的食品非热除菌技术手段,利用光生的活性氧自由基(reactive oxygen species,ROS)攻击微生物细胞的多个靶点,不易产生耐药性,在鲜切菜领域展现出了巨大的应用前景,为当前研究的前沿热点。考虑到鲜切菜本身具有的生理活性成分与光敏剂之间的相互作用,相比离体实验,PDAT在鲜切菜中的应用效果有限,应将其视为额外的除菌工具,而不是其他传统除菌技术的替代品。本文以鲜切菜的食品安全为出发点,综述了PDAT的原理、方法优势及劣势,鲜切菜的代谢生理变化与PDAT在鲜切菜领域上的应用研究进展与未来发展方向,以期为促进净菜产业的食品安全和PDAT的发展提供依据。

紫外发光二极管(UV-LED)技术对食品微生物灭活应用的研究进展

紫外辐照是一种非热杀菌技术,汞蒸气紫外灯是现阶段用于食品卫生处理的主要设备,但受某些因素影响,汞灯的生产使用将逐渐变少,被环保节能的紫外发光二极管(UV-LED)取代是一种不可避免的趋势。本文根据UV-LED发光原理和多波长耦合应用的特点,综述了对微生物灭活的机理、探究了影响灭活效果的因素(波长、紫外剂量和物料特性)、处理食品的灭菌效果以及对部分食品品质的影响,为UV-LED在食品领域的杀菌处理工艺和设备参数优化提供参考。

Application of Ceramic Coat Synthesized by In-Situ Combustion Synthesis to BF Tuyere

A novel technology of tuyere protection is introduced. The ceramic coat .is synthesized by using in-situ combustion process as the internal, external, and nose protecting coat of BF tuyeres. It can effectively protect the tuyeres and reduce heat loss by cooling water. The technglogy is quick-acting, easy to use, energy-saving and can make tuyeres have long service life. The feasibility of the application of the tuyere ceramic coat is discussed and the energy-saving effect of the tuyere is compared with that of the tuyeres lined with refractory.

Measures for controlling large deformations of underground caverns under high in-situ stress condition--A case study of JinpingⅠhydropower station

The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics.

In-situ Fabricated TiB_2 Particle-whisker Synergistically Toughened Ti(C,N)-based Ceramic Cutting Tool Material

The mechanical properties of ceramic cutting tool materials can be modified by introducing proper content of nanoparticles or whiskers.However,the process of adding whiskers or nanoparticles has the disadvantages of high cost and health hazard as well as the agglomeration;although a new in-situ two-step sintering process can solve the above problems to some extent,yet the problems of low conversion ratio of the raw materials and the abnormal grain growth exist in this process.In this paper,an in-situ one-step synthesis technology is proposed,which means the growth of whiskers or nanoparticles and the sintering of the compact can be accomplished by one time in furnace.A kind of Ti（C,N）-based ceramic cutting tool material synergistically toughened by TiB_2 particles and whiskers is fabricated with this new process.The phase compositions,relationships between microstructure and mechanical properties as well as the toughening mechanisms are analyzed by means of X-ray diffraction（XRD）and scanning electron microscopy（SEM）.The composite which is sintered under a pressure of 32 MPa at a temperature of 1700℃in vacuum holding for 60 min can get the optimal mechanical properties.Its flexural strength,fracture toughness and Vickers hardness are 540 MPa,7.81 MPa·m（1/2）and 20.42 GPa,respectively.The composite has relatively high density,and the in-situ synthesized TiB_2 whiskers have good surface integrity,which is beneficial for the improvement of the fracture toughness.It is concluded that the main toughening mechanisms of the present composite are whiskers pulling-out and crack deflection induced by whiskers,crack bridging by whiskers/particles and multi-scale particles synergistically toughening.This study proposes an in-situ one-step synthesis technology which can be well used for fabricating particles and whiskers synergistically toughened ceramic tool materials.

Development of an Environmentally Friendly in-situ Pack-Cyaniding Technique

A safe and environmentally friendly cyaniding method has been developed to mitigate the toxic impacts of cyanide salts on the environment during conventional cyaniding. The method entails in-situ diffusion of nascent cyanide from mature cassava leaves into the surface of mild steel components via pack-cyaniding. Both high-temperature in-situ diffusion into austenite and low-temperature in-situ diffusion into ferrite were explored. Results from light and scanning electron microscopic studies showed that surface hardness of the steel components was substantially increased. The waste product was a harmless biodegradable organic compound that posed no disposal threats. This study is important for increasing the wear resistance of ferrous parts for a longer service life in application without polluting the environment.

燕麦、荞麦、青稞面条品质影响因素及其改良研究进展

杂粮由于富含纤维以及较多的生物活性成分而受到越来越多的关注和认可,包括杂粮面条在内的杂粮产品开发也逐渐成为食品行业的研究热点。文章介绍了燕麦、荞麦、青稞3种杂粮的营养成分,分析了营养成分对面条品质的影响,并重点介绍了工艺改良、添加品质改良剂、灭酶、抑菌等改良手段,最后对现有研究中存在的问题进行了分析并提出了今后的重点研究方向,以期为燕麦、荞麦、青稞的深度开发提供依据。

鸡新城疫的诊断与防控技术

鸡新城疫一直是家禽养殖行业重点关注的动物疫病。近年来,有关非典型性鸡新城疫疫情的报道不断增加,养殖者需制定合理的防控方案,根据本场实际情况进行科学疫苗免疫,定期监测鸡群免疫水平;加强饲养管理,建立养殖场生物安全体系和信息化预警体系;中西医结合增强免疫效果,使鸡群新城疫抗体水平维持在较高水平。文章介绍了鸡新城疫的流行特点、临床症状、病理变化及实验室检测方法,提出相关防治措施,以期为鸡新城疫的防控提供参考。

马铃薯片微波灭酶最佳工艺参数

研究了微波源阳极电流、微波作用时间、马铃薯片厚度3个因素对马铃薯片综合品质的影响规律,采用二次回归正交旋转组合设计法,借助响应面分析得出最佳工艺参数为:微波源阳极电流161.78 mA、微波作用时间10.19 s、马铃薯片厚度为2.88 mm。使用最佳工艺参数进行验证,回归模型的拟合度较好。说明使用最佳工艺参数,可使微波灭酶技术既能降低马铃薯片多酚氧化酶的活性,又能保持良好的感官品质。

牡蛎中诺如病毒的感染及其防控研究进展

诺如病毒(Norovirus, NoV)是非细菌性急性胃肠炎的主要病原体。牡蛎可通过滤食作用富集海水和环境中污染的NoV,是NoV传播的重要载体。人们倾向于食用生的或轻微烹煮的牡蛎,导致NoV感染事件时有发生。与牡蛎相关的食源性疾病中,约50%由NoV引起。荧光定量PCR是检测NoV的主要方法,但其不能有效区分感染性与非感染性NoV。由于NoV难以在体外培养,致使评估NoV灭活方法的有效性存在困难。猪胃黏蛋白(Porcine gastric mucin, PGM)及叠氮溴化丙锭(Propidium monoazide, PMA)等核酸嵌入剂与qPCR结合的方法在检测感染性NoV中显现出应用潜力。牡蛎中NoV的消减方式多为超高压处理,400 MPa及以上的压力可使NoV大量灭活。文章综述了近年来牡蛎[主要是太平洋牡蛎(Crassostrea gigas)、褶牡蛎(Alectryonella plicatula)和熊本牡蛎(C. sikamea)]中NoV的污染状况、富集机制、检测方法以及超高压处理消减NoV等方面的研究成果,为建立牡蛎中NoV有效的风险预警和控制技术提供参考。

超高压联合其他保鲜技术在水产品中应用的研究进展

水产品捕捞后,由于微生物与内源酶的作用,在脂肪氧化等其他因素的影响下,感官品质下降,采用适当的处理手段可以延缓其劣变。超高压技术具有压力传递均匀、杀菌效果好、灭酶彻底等特点,能保全食品加工前的色泽、香味及各类营养成分,同时还可以赋予食品新的口感,具有低能耗、高效率、无二次污染、操作简便等优点。在介绍超高压处理技术主要优缺点、工作原理与作用机制的基础上,阐述了该技术在水产品灭菌、钝酶与加工改性等方面的应用研究进展,提出超高压处理可联合物理、化学及生物保鲜技术提升作用效果,并对超高压技术在水产品中的发展前景予以展望。

核黄素光化学作用灭活大肠杆菌的研究

目的研究核黄素光化学反应对细菌的灭活作用,探讨分析核黄素光化学灭活病原体的机理。方法将含有细菌的培养液4.950ml注入5ml血袋中,再加入10mmol/L的核黄素溶液50μl使其终浓度为100μmol/L,将血袋置控温光照仪中接受400—500nm波段可见光双侧照射[剂量(8.0—32.0)J/cm2],照射时温度为(4±2)℃;照射后标本通过细菌培养,透射电镜影像、核酸检测(LacZ基因片段)等方法观察核黄素光化学作用灭活大肠杆菌的效果。结果400—500nm可见光激发的核黄素光化学作用可以有效灭活大肠杆菌达6log;透射电镜影像示经核黄素光化学处理的大肠杆菌其拟核所在区域出现多个空泡;PCR显示经核黄素光化学处理的大肠杆菌其LacZ基因片段的复制被完全阻止。结论可见光激发的核黄素光化学作用可以有效灭活大肠杆菌,核酸是核黄素光化学产生病原体灭活作用的主要靶点。

核黄素光化学法灭活Sindbis病毒的研究

目的探究核黄素光化学反应对Sindbis病毒的灭活效果。方法将10 mmol/L的核黄素0.050 mL加入到4.95 mL的Sindbis病毒(XJ-160株)悬液中,经440 nm波段的可见光(40 J/cm2)双侧照射后,接种至幼仓鼠肾细胞(BHK-21)中培养,观察细胞病变情况(CPE),检测病毒滴度,用PCR检测病毒核酸的变化,并在透射电镜下观察病毒形态。结果经终浓度为100μmol/L核黄素结合440 nm可见光作用,可将滴度为6.5 log TCID50Sindbis病毒灭活至≤0.5 logTCID50;PCR法未能扩增出病毒核酸片段;透射电镜显示病毒颗粒塌陷。结论核黄素光化学法能有效灭活Sindbis病毒,其主要作用靶点为核酸。

血液及血液制品病原体灭活/去除的必要性和可行性

血液中可能存在的病原体可能导致输血发生感染性风险。血液筛查技术和血液管理措施并不能完全消除这种残余性风险,因此血液及血制品的病原体灭活/去除是保障输血安全的另一条重要防线。病原体灭活/去除技术是否可行,须从1)有效去除血液中的目标病原体、2)对被处理血液成分的治疗效果无明显不良影响、3)对人体安全、4)技术可行性和法规的符合性等4个方面来考量,同时做必要的卫生经济学分析。仅仅由于成本原因而未能采用或不考虑采用诸如病原体灭活/去除等适宜的血液安全技术,无异于本末倒置,无论对输血安全的整体形势还是对接受输血的病患者个人来说,都是有害无益的。

肠道病毒71型灭活疫苗生产中氢氧化铝佐剂制备工艺优化

目的:对肠道病毒71型灭活疫苗生产工艺中氢氧化铝佐剂的制备工艺进行优化。方法:采用氨水法制备氢氧化铝佐剂,取优化前3批及优化后3批,对制备过程中氨水的滴加方式以及透析方式进行优化;检测优化前后的氢氧化铝佐剂的粒径、沉降率、铵离子及铝含量,同时检测优化前后各3批氢氧化铝对肠道病毒71型灭活疫苗的吸附效果。结果:优化后的氢氧化铝佐剂平均粒径显著小于优化前(P<0.05),且平均粒径变异系数小于优化前3批,优化后3批氢氧化铝佐剂的沉降率均为0 m L,铵离子检测合格率100%,铝含量及氢氧化铝含量显著大于优化前(P<0.05)、分别提高了24.7%和26.1%;优化前后6批氢氧化铝佐剂所配制的半成品,其上清液抗原百分含量均≤1.25%,优化前后的氢氧化铝佐剂对EV71抗原的吸附效果比较,差异无统计学意义(P>0.05)。结论:本部分的优化方式提高了自配氢氧化铝佐剂的质量和安全性,减少了批间差异,提高了生产效率,并且其有效性没有因为优化而受到影响。