地中海饮食一直被誉为"健康饮食的典范",橄榄油是这一饮食模式的主角之一.近期,西班牙多家机构的两项研究表明,饮食中加入橄榄油能起到减脂和消炎的作用,即使将橄榄油高温加热烹制,仍能保持其抗氧化、防衰老的效果.

水利工程是为实现水资源在地域、时空上的重分配,起到蓄洪、发电、航运、供水、灌溉等一系列工作的重要工程.随着社会的进步,水利工程发挥的作用愈发显著,其对生态环境的影响也越来越大.本文系统分析了水利工程对环境的几大重要影响,针对特定影响,简要介绍了一些广泛使用的控制措施.并联系我国国情,适当探讨了我国在某几个领域上存在的欠缺.

中国古人治水历史悠久,创造了许多治水奇迹,部分水利工程虽历经千年,却仍在发挥作用,其治水理念、思想和智慧具有极大的研究价值以及丰富的学习、借鉴意义.文章先简要论述了中国古人对水的理解,随后通过具体案例的分析,探讨其治水理念,最后指出这些理念对现代治水的影响.

吃饭太快发胖风险高 日本一项研究表明,吃饭速度才是导致发胖不容忽视的因素,并对健康产生极大影响.研究小组以大学生为对象,就肥胖和进食方式之间的关系进行了为期三年的跟踪调查.结果显示,在热量水平差别不大的情况下,"快食"(吃饭速度快)者与吃饭速度正常者相比,发胖风险高了4.4倍,吃饭快的男性比女性受影响更大.研究人员指出,迄今为止关于肥胖和快食的关系均为短暂的横向观察,像本次研究对同一对象进行长年纵向研究尚属全球首次.

Radionuclides in upper reactor container,pool materials,resin and waste were surveyed on the decommissioning site of Jinan Miniature Neutron Source Reactor,and the survey of pool materials was described in detail.The radionuclides in surveyed materials include 60Co,152Eu,137Cs and 54 Mn with higher activity concentrations in materials at pool bottom just below the reactor container.The survey results indicate that upper reactor container,resin for reactor water purification,waste and a part of pool materials are low level waste.A certified reference material GBW08304awas used in this survey for quality control.The measured values agree well with the standard values within±15%.

In-hospital neutron irradiator(IHNI) was specially designed for boron neutron capture therapy(BNCT).On the both sides of the reactor core,there are two neutron beams.One is thermal neutron beam,and the other opposite to the thermal beam,is epithermal neutron beam.A small thermal neutron beam is specially designed for the measurement of blood boron concentration by the prompt gamma neutron activation analysis(PGNAA).The six experiments were completed during startup.The results show that the maximum continuous operation time at full power is 12 h,and the final excess reactivity is 4.2 mk.The radiation dose rates at different rooms meet the designed requirement.When the positive reactivity with 4.2 mk is inserted into the reactor suddenly,the power will increase to peak power,and then,it will turn to the normal value due to the negative temperature effect,and the release result of reactivity shows the inherent safety of IHNI.

In-hospital Neutron Irradiator (IHNI) was specially designed for Boron Neutron Capture Therapy (BNCT), the rated power of IHNI is 30kW, corresponding to the neutron flux density 1×1012n·cm−2·s−1 in reactor core. IHNI is an undermoderated reactor of pool-tank type, and UO2 with enrichment of 12.5% as fuel, light water as coolant and moderator, and metallic beryllium as reflector. The fission heat produced by the reactor is removed by the natural convection. On the both sides of the reactor core, there are two neutron beams, one is thermal neutron beam, and the other opposite to the thermal beam, is epithermal neutron beam. A small thermal neutron beam is specially designed for the measurement of blood boron concentration by the Prompt Gamma Neutron Activation Analysis (PGNAA). The decay constants and shares of six group of ordinary delayed neutron and nine group of photoneutron were obtained by WIMS code. Based on that, the relationship between the reactivity and the reactor period was calculated through the inhour equation. In this way, the excess reactivity and the reactivity worthies of the components (control rod, water, etc) in the core are obtained by periodic method during the startup of the reactor. The six test experiments were completed during startup, The test results show that the maximum continuous operation time at full power is 12h; the excess reactivity at cold clean state of the core is 4.2mk; The radiation levels at technical rooms are within the specified values at full power operation. When the positive reactivity with 4.2 mk is inserted into the reactor suddenly, the power will be increased to peak power, and then, it will turn to the normal value due to the negative temperature effect, this experiment shows the inherent safety of IHNI.

夏大豆植株小,生育期短,要想在有限的时间内获得较高的产量,田间管理上应当以促为主,做到“三早两巧”. 1.早间苗,匀留苗.夏大豆苗期短,要早间苗,早定苗.当亩高3厘米时,结合中耕间苗定苗,每亩定苗密度略大于3万株,间苗和定苗要一次完成.

The transmutation reaction rate of the 9 kinds of MA and LLFP nuclides were calculated based on ADS subcritical facility Venus 1#.The transmutation reaction rate of 137Cs in the fast-thermal coupled zone was measured,and the transmutation speed of 137Cs was 10 times to natural decay.The results that Venus 1# has a certain transmutation ability,and the calculated result of the transmutation reaction rate for 137Cs agrees with the measuring result.

In-Hospital Neutron Irradiator(IHNI) is the first miniature neutron source reactor for special medical treatment purpose.It got critical on December 7th,2009,and went to full power on January 22th,2010.Parameters,such as the neutron flux density and neutron spectrum of the thermal neutron beam in IHNI,should be given before the medical treatment.Model was built and calculation results were given by MCNP program.The neutron flux density was measured by gold foil activation technique,and the neutron spectrum was measured by multiple foils activation technique and unfolded by SAND-Ⅱ program.Detectors were irradiated and then measured by HPGe.Neutron flux density and distribution was given,and neutron spectrum was unfolded with SAND-Ⅱ program.

A DAQ system of current signal with very low and wide range, which has the ability of detecting the reactor neutron signal, was designed. A chopper-stabilized OP-Amp was used as the main amplifier, the data selector was used as the main unit of gain selector, and the SoC C8051F020 was used as ADC system and control unit. The current range of this system is 10-11-10-6 A, this range is divided into six grades, and it can be switched automatically. This system has the ability of communication with PC through UART. The design test was completed on prototype miniature neutron source reactor (MNSR), and the test results show that the design is reasonable.

春末夏初,气温逐渐升高,是自然界病原微生物如细菌、病毒大量繁殖之时,若不留意,极易引发传染病.当然,最常见的就是小儿"准"呼吸道传染病.那么,有人会问,传染病就传染病呗,这个"准"字又是什么意思呢?我们不妨先看看下面几个例子.

The construction of in-hospital neutron irradiator (IHNI) started in 2007. Its building construction was completed in Dec. 2008, and the installation and test of the relevant systems were completed in Mar. 2009. The first criticality was achieved on Dec. 7, 2010. The reactor reached the full power on Jan. 22, 2010. The test results show that the final excess reactivity is 4.2 mk; the maximum continuous operation time at full power is 12 h and the power wave is less then 0.3 % during full power operation; when the positive reactivity with 4.2 mk is inserted into the reactor suddenly, the power will be increased to 85.7 kW at the time of 229 s, and then, it will turn to the normal value due to the negative temperature effect.The release result of reactivity shows the inherent safety of reactor.

In 2010, the commissioning of in-hospital neutron irradiator (IHNI) and its systems were completed. The operation with power started since then. The IHNI has operated by 99 times. The release of total energy is 1 832.42 kW·h with the corresponding integral neutron flux of 2.198 9×1017 cm-2. The test operation data shows that the operation values of IHNI and its relevant systems are smaller than the limited value, which manifests that IHNI is safe and reliable.

The design of in hospital neutron irradiator (IHNI) and its systems were introduced, and the performance and characteristics of IHNI were described. In order to test the inherent safety of IHNI, the experiment of 4.2 mk reactivity release was done. The experimental results showed that the peak power of IHNI was 85.7 kW at the time of 229 s after 4.2 mk reactivity release, and then, the power decreased owing to the negative temperature coefficient of moderator. The radiation dose rates at different rooms were lower than the standard value.

Relative neutron count rate change was studied on Venus 1# sub-critical assembly for the detectors at different positions of the core with external neutron source,Am-Be neutron source and 252Cf neutron source respectively.The experimental results show that neutron count rate changes for the detectors at different positions are different on Venus 1# sub-critical assembly,but it’s little effect on the results of sub-critical extrapolate experiment.

In the paper,the Venus 1# sub-critical assembly,configuration of reactor core,the external neutron source system and the neutronics research experiment system about accelerator driven sub-critical system (ADS) were introduced.The sub-criticality of reactor was studied using Source-Jerk method at different loadings.The results of measurement were compared with calculated results,and they are in agreement well.

<正>医院中子照射器是利用中子俘获疗法(NCT)原理,治疗癌症的世界首台核医疗装置。在完成了有关A阶段调试工作后,并获得国家核安全局装料许可后,于2009年12月7日顺利安全地达到了临界。首次临界实验采用水位法,根据有关法规第1次添加7L去离子水,第2次添加4L去离子水,然后,根据外推临界水量进行逐次添加水量。最终,临界水量为25.4L。在超临界内