豚鼠离体小肠电活动与机械收缩

以小肠电活动和环肌张力、纵肌张力为指标，用同步记录的方法研究了豚鼠离体小肠电活动与环肌张力、纵肌张力之间的关系，结果表明：（１）豚鼠离体小肠的电活动包括慢波与峰波；（２）豚鼠离体小肠始终存在着节律性张力活动，其环肌收缩与纵肌收缩的关系表现为拮抗收缩、共同收缩、交互抑制等形式；（３）峰波可增加收缩力，峰波的个数、振幅与小肠张力呈正变关系，尤其与环肌收缩的对应关系更为显著．（４）慢波可触发收缩，尤其是纵肌收缩．在没有峰波仅有慢波时，亦可有收缩活动甚至活跃的收缩活动．     

铁肥品种和施肥方式对苹果树体内叶绿素和铁含量的影响

铁胁迫致苹果黄叶时进行根系输铁液能在较短时间内提高叶片叶绿素和铁的含量从而达到复绿的效果。在Ｆｅ－Ｃｉｔｒｉｃ ａｃｉｄ、Ｆｅ－ＥＤＴＡ 和Ｆｅ－Ｎ ３ 种铁肥中，Ｆｅ－Ｎ 是适宜根系输液的铁肥品种，主干强力高压注射铁肥复绿较慢，叶面喷布效果不显著。     

烧结工艺对含硅锰烧结钢性能与组织的影响

研究了烧结温度和时间对Ｆｅ－３．１Ｍｎ－１．２Ｓｉ－０．４Ｃ烧结刚性能与组织的影响，实验结果表明：提高烧结温度和延长烧结时间都能改善Ｆｅ－３．１Ｍｎ－１．２Ｓｉ－０．４Ｃ烧结钢的机械性能；并使烧结试样由膨胀逐渐向收缩过渡，Ｆｅ－３．１Ｍｎ－１．２Ｓｉ－０．４Ｃ烧结网在１１００℃以上烧结时，由于有液相的出现，合金化过程可以被大大地提高，在烧结过程中，只有那些较小的硅锰母合金颗粒才能全部熔化，而那些尺     

纺锤形铁黄α－FeOOH微晶合成动力学研究

本文对纺锤形α－ＦｅＯＯＨ微晶合成动力学过程进行了研究．利用复相反应经验动力学方程，考察了初始浓度、反应温度和空气流量对Ｆｅ（ＯＨ）２－ＰｅＣＯ３悬浮液氧化速率的影响，确定了α－ＦｅＯＯＨ成核－生长速率方程，证实了晶粒生长阶段存在溶解－氧化的动态平衡，根据活化能大小，推断相界面氧化反应为该复相反应的控制步骤，还对α－ＦｅＯＯＨ成核生长微观机理作了初步探讨．     

Fe6（CO）14（μ—CO）3（μ—η^2—OOCNC6H11）的合成和表征

（Ｎ（Ｐ（Ｃ６Ｈ５）３）２（ＨＦｅ３（ＣＯ）１１）与异氰酸苯酯反应，酸化后给出了簇合物Ｆｅ６（ＣＯ）１４（μ－ＣＯ）３－（μ－η＾２－ＯＯＣＮＣ６Ｈ１１）异氰酸苯酯的Ｃ＝Ｏ双键劈开加氧，以（μ－η＾２－ＯＯＣＮＣ６Ｈ１１）形式配位于２个铁原子，异氰酸苯酯的苯加氢还原子为环己烷，同时表征了产物的ＩＲ，＾１ＨＮＭＲ和ＭＳ谱。     

KNbO3陶瓷的半导化及PTC效应

采用添加钾锗玻璃和掺ＭｏＯ３的方法，制备了ＫＮｂＯ３半导瓷，在此基础上，对ＫＮｂＯ３半导瓷样品进行了电学性能的测试以及样品断面形貌的扫描电镜观察和分析。结果表明，两种方法制备的ＫＮｂＯ３半导瓷样品都在铌酸钾晶体的两个相变点附近出现了ＰＴＣ电阻异常：一个在正交铁电相－－四方铁电相转变处；另一个在四方铁电相－－立方顺电相转变处，而掺ＭｏＯ３制备的半导瓷具有较小这曙电阻率及较大的电阻率反常幅度（ＦＥ－Ｆ     

黄芪多糖对荷瘤小鼠红细胞免疫功能的影响

采用红细胞Ｃ３ｂ受体花环率（ＲＢＣ－Ｃ３ｂＲＲ），红细胞免疫复合物花环率（ＲＢＣ－ＩＣＲＲ），血清中红细胞Ｃ３ｂ受体花环抑制率（ＲＥＩＲ）和红细胞Ｃ３ｂ受体花环促进率（ＲＦＦＲ）等四个指标，研究了黄芪多糖对Ｓ１８０Ａ小鼠肝癌（ＨＥＰＡ）和小鼠红细胞免疫功能的影响。结果表明，黄芪多糖能明显提高荷瘤小鼠的ＢＢＣ－Ｃ３ｂＲＲ和ＲＦＥＲ，降低ＲＢＣ－ＩＣＲＲ和ＲＦＩＲ。这一结果说明黄芪多糖对荷瘤小鼠红细胞免疫有明显的促进作用。     

包钴包亚铁磁粉表面的XPS研究

使用ＶＧ ＥＳＣＡＬＡＢ５电子能谱仪对不同产地的ＣｏＦｅ－γ－Ｆｅ２Ｏ３磁粉的表面进行了研究，对不同ＣｏＦｅ－γ－Ｆｅ２Ｏ３磁粉表面Ｃｏ，Ｆｅ元素的可能价态和组分进行了分析，探讨了包钴包亚铁磁粉采用的工艺。     

微量元素对高速电镀锌—镍合金的影响

研究了微量元素Ｃｕ，Ｆｅ，Ｃｒ对高速电镀Ｚｎ－Ｎｉ合金的影响并探讨了其作用机理。Ｃｕ＾２＋在Ｚｎ－Ｎｉ镀液中容易析出，但它是一种有害元素，Ｆｅ＾２＋，Ｃｒ＾３＋则难于析出，镀层中含适量的Ｆｅ，Ｃｒ可提高Ｚｎ－Ｎｉ镀层耐蚀性。同时还探讨了微量元素电沉积机理，提出了微量元素从Ｚｎ－Ｎｉ镀液中电沉积进入镀层的定量判定方法。     

用低温等离子体技术降解三氟溴甲烷（哈隆1301）

利用低温等离子体技术对三氟溴甲烷ＣＦ３Ｂｒ进行了降解。在放电３ｍｉｎ后，ＣＦ３Ｂｒ的降解率可达５５％，而在ＣＦ３Ｂｒ－Ｏ２体系中，ＣＦ３Ｂｒ的降解率可达６８％。研究了低压ＣＦ３Ｂｒ的气相反应机理，以及ＣＦ３Ｂｒ初妈压力，外加气体对降解ＣＦ３Ｂｒ的影响。     

基于视觉暂留原理的旋转式线阵LED显示屏开发

基于“视觉暂留”原理,开发出了一种旋转式线阵LED显示屏。从机械与电气两个方面介绍了该LED显示屏的设计。重点介绍了轴套的设计及软件设计,实现了显示屏转动与屏幕显示内容出现时序的匹配。该显示屏具有原理应用巧妙、成本降低、解析度提高、节省能源等特点。     

干缩法、力学法、电学法测定木材纤维饱和点的研究

<正>本文利用干缩法、力学法、电学法分别对针叶树马尾松、阔叶树钩栗的纤维饱点作了测试,得出了与经典的纤维饱和点相近的数值,并对干缩法、力学法、电学法的测试方法作了探索。通过实验曲线和理论推导得出了干缩法测定纤维饱和点的简便公式,它不仅减轻了测量的工作量,而且进一步提高了测量精度。同时,对这三种测定方法的利弊进行了较系统的分析和比较。     

生命不止,能量不息——植入式摩擦纳米发电机的研究与应用

 2012年,研究人员提出了一种将机械能转化为电能的摩擦纳米发电机（TENG）,该技术近年来得到了飞速发展,实现了对人体运动能、风能、声波能、海洋能等各种机械能的收集。其中植入式摩擦纳米发电机（iTENG）可将生物体内的心跳、呼吸肌运动等生物机械能转化为电能并驱动有源植入式医疗器件,可显著提高可植入式医疗器件的使用寿命,在未来植入式医疗行业中有着潜在的应用前景。本文综述了iTENG的结构、工作原理、输出性能及其在有源植入式医疗器件供能应用等方面的最新研究进展,并在此基础上进一步分析iTENG应用到临床治疗所面临的挑战。     

Reversible electromechanical characteristics of carbon nanotubes under local-probe manipulation

The effects of mechanical deformation on the electrical properties of carbon nanotubes are of interest given the practical potential of nanotubes in electromechanical devices, and they have been studied using both theoretical and experimental approaches. One recent experiment used the tip of an atomic force microscope (AFM) to manipulate multi-walled nanotubes, revealing that changes in the sample resistance were small unless the nanotubes fractured or the metal-tube contacts were perturbed. But it remains unclear how mechanical deformation affects the intrinsic electrical properties of nanotubes. Here we report an experimental and theoretical elucidation of the electromechanical characteristics of individual single-walled carbon nanotubes (SWNTs) under local-probe manipulation. We use AFM tips to deflect suspended SWNTs reversibly, without changing the contact resistance; in situ electrical measurements reveal that the conductance of an SWNT sample can be reduced by two orders of magnitude when deformed by an AFM tip. Our tight-binding simulations indicate that this effect is owing to the formation of local sp3 bonds caused by the mechanical pushing action of the tip.     

Contractile force measured in unskinned isolated adult rat heart fibres

A number of investigators have succeeded in preparing isolated cardiac cells by enzymatic digestion which tolerate external [Ca2+] in the millimolar range. However, a persistent problem with these preparations is that, unlike in situ adult ventricular fibres, the isolated fibres usually beat spontaneously. This spontaneity suggests persistent ionic leakage not present in situ. A preferable preparation for mechanical and electrical studies would be one which is quiescent but excitable in response to electrical stimulation and which does not undergo contracture with repeated stimulation. We report here a modified method of cardiac fibre isolation and perfusion which leaves the fibre membrane electrically excitable and moderately resistant to mechanical stress so that the attachment of suction micropipettes to the fibre is possible for force measurement and length control. Force generation in single isolated adult rat heart fibres is consistent with in situ contractile force. The negative staircase effect (treppe) characteristic of adult not heart tissue is present with increased frequency of stimulation. Isometric developed tension increases with fibre length as in in situ ventricular tissue.     

Mechanically driven ATP synthesis by F1-ATPase

ATP, the main biological energy currency, is synthesized from ADP and inorganic phosphate by ATP synthase in an energy-requiring reaction. The F1 portion of ATP synthase, also known as F1-ATPase, functions as a rotary molecular motor: in vitro its gamma-subunit rotates against the surrounding alpha3beta3 subunits, hydrolysing ATP in three separate catalytic sites on the beta-subunits. It is widely believed that reverse rotation of the gamma-subunit, driven by proton flow through the associated F(o) portion of ATP synthase, leads to ATP synthesis in biological systems. Here we present direct evidence for the chemical synthesis of ATP driven by mechanical energy. We attached a magnetic bead to the gamma-subunit of isolated F1 on a glass surface, and rotated the bead using electrical magnets. Rotation in the appropriate direction resulted in the appearance of ATP in the medium as detected by the luciferase-luciferin reaction. This shows that a vectorial force (torque) working at one particular point on a protein machine can influence a chemical reaction occurring in physically remote catalytic sites, driving the reaction far from equilibrium.     

Expression of apamin receptor in muscles of patients with myotonic muscular dystrophy

Myotonic muscular dystrophy, or Steinert disease, is a dominantly inherited disease of muscle which occurs with a frequency of between 1 in 18,000 and 1 in 7,500 people (refs 1, 2). One of the prominent clinical manifestations is muscle stiffness and difficulty in relaxation of muscles after voluntary contractions. Electrophysiological signs of myotonia include increased excitability with a tendency to fire trains of repetitive action potentials in response to direct electrical and mechanical stimulation. Most experimental and clinical data suggest that myotonic muscular dystrophy arises from genetically induced alterations of the muscle membrane. We show here for the first time that muscle membranes of patients with myotonic muscular dystrophy contain the receptor for apamin, a bee venom toxin known to be a specific and high-affinity blocker of one class of Ca2+-activated K+ channels in mammalian muscle. The apamin receptor is completely absent in normal human muscle as well as in muscles of patients with spinal anterior horn disorders.     

The corticomotoneurone connection is normal in Parkinson's disease

Voluntary movements in Parkinson's disease are initiated and executed slowly. It is assumed that the motor cortex and its output pathway are intact and that bradykinesia is due to abnormal motor commands delivered to a normal corticospinal system. We have tested this assumption using electrical stimulation of the motor cortex through the scalp in three patients with severe Parkinson's disease, studied during fluctuations from relatively normal mobility when receiving drugs (ON) to severe bradykinesia when not receiving drugs (OFF). Thresholds and latencies for motor cortex stimulation to excite thumb flexor muscles and the resulting fast mechanical responses were the same in both ON and OFF conditions, even though the patients were unable to execute fast thumb flexion movements voluntarily when OFF. We conclude that the excitability and conduction velocity of the corticospinal motor pathways are normal in Parkinson's disease.     

Restoration of grasp following paralysis through brain-controlled stimulation of muscles

Patients with spinal cord injury lack the connections between brain and spinal cord circuits that are essential for voluntary movement. Clinical systems that achieve muscle contraction through functional electrical stimulation (FES) have proven to be effective in allowing patients with tetraplegia to regain control of hand movements and to achieve a greater measure of independence in daily activities. In existing clinical systems, the patient uses residual proximal limb movements to trigger pre-programmed stimulation that causes the paralysed muscles to contract, allowing use of one or two basic grasps. Instead, we have developed an FES system in primates that is controlled by recordings made from microelectrodes permanently implanted in the brain. We simulated some of the effects of the paralysis caused by C5 or C6 spinal cord injury by injecting rhesus monkeys with a local anaesthetic to block the median and ulnar nerves at the elbow. Then, using recordings from approximately 100 neurons in the motor cortex, we predicted the intended activity of several of the paralysed muscles, and used these predictions to control the intensity of stimulation of the same muscles. This process essentially bypassed the spinal cord, restoring to the monkeys voluntary control of their paralysed muscles. This achievement is a major advance towards similar restoration of hand function in human patients through brain-controlled FES. We anticipate that in human patients, this neuroprosthesis would allow much more flexible and dexterous use of the hand than is possible with existing FES systems.     

F.C道路材料的实用性研究

Ｆ．Ｃ材料是一种新型筑路材料，与普通混凝土相互，具有良好的物理力学性能。钢纤维、钢丝钢复事型混凝土的实研究为现代路面工程拓宽了领域。