减压冷藏保鲜贮藏装置的一种湿度补偿方法

介绍了减压保鲜贮藏装置的一种湿度补偿系统,适用于对减压冷藏保鲜贮藏装置进行的湿度补偿。     

淋水式冷风机湿冷系统设计及性能实验研究

针对果蔬、花卉等的预冷、冷藏湿冷保鲜技术过程要求,在综合分析了目前流行的冰水湿冷系统特点的基础上,设计了淋水式冷风机湿冷系统,测试了该系统的综合性能。结合测试结果,从理论上重点分析了该系统的预冷冷却的动态过程和相对稳定的冷藏保鲜过程。结果表明:该系统不但能够较好地实现果蔬预冷冷却过程的高湿和相对稳定的冷藏保鲜过程的高湿(>92%RH)、低温(3~6℃)的环境,而且系统设备结构紧凑,更有利于果蔬湿冷保鲜技术进一步的推广应用。     

果蔬减压冷藏预冷过程的初步研究

国内外对许多果蔬做了大量实验,并给出了一些果蔬减压预冷的实验结果,但由于缺乏过程参数(如压力、温度等)的变化说明,制约着减压冷藏技术的应用.为此,选择生菜、菜心、樱桃分别代表三种典型果蔬,对其减压冷却过程分别进行初步研究和讨论,得到适合三类果蔬减压冷藏预冷的一般性结论,明确了典型果蔬预冷技术后续的研究方向和工作目标.     

真空预冷技术在茶树菇冷藏保鲜上的应用研究

本研究将真空预冷技术配合塑料薄膜袋包装应用于冷藏保鲜茶树菇的预处理,研究该技术对冷藏保鲜的辅助作用,并筛选出最佳预处理工艺条件。结果表明：采用真空室的真空度350Torr,真空预冷终温0℃,真空预冷时间20min,进行真空预处理并配合塑料薄膜袋包装的茶树菇比一般的冷藏保鲜效果明显更好。表现在：冷藏十天不开伞、不干缩、表面膜不脱落、失重率减少7％,呼吸强度曲线明显下移,呼吸高峰推迟2d出现,峰值降低30％,VitC保存率提高20．5％。     

一种简单有效的减压保鲜贮藏实验装置

介绍了一种真空减压保鲜装置及其工作原理,对真空减压保鲜装置真空系统、制冷系统、测量和控制系统的组成,设备的选用等进行了分析和讨论,据此对减压保鲜贮藏实验装置进行了设计和搭建,安装检测控制系统。所介绍的真空减压保鲜实验设置简洁实用,能够对保鲜冷藏作出参数定性研究和初步的参数定量研究。     

冷间内交互预冷系统的设计与研究

预冷是提高果蔬贮藏保鲜质量的重要技术措施之一,但常见的预冷方式存在二次搬运费工费时、增加二次损伤及设备闲置与浪费的缺点。冷间内交互预冷系统是一种冷藏间之间的交互预冷方式,避免了二次搬运,减少了预冷设备闲置,节省了设备投资。     

多功能果蔬保鲜装置的研制及大白菜真空预冷实验

本文介绍了一种兼具"真空预冷、减压贮藏、冰温真空干燥"三个功能于一体的果蔬保鲜装置及其工作原理,并对该装置的真空系统、制冷系统、加湿换气系统、控制系统的组成及工作过程进行了详细介绍与分析。利用该装置做了大白菜真空预冷及减压贮藏实验,结果表明,随着舱内压力的降低大白菜真空预冷过程可分为三个阶段:温度缓降、温度骤降及温度持平阶段;以大白菜失水率3.34%等实验数据分析了此装置的技术特点和独特优势。该装置可以从预冷、贮藏两个阶段缩短冷链物流的运转周期,减少果蔬搬运造成的机械损伤,从而将在商业化普及应用中创造更多的经济效益。     

减压保鲜油豆角实验研究

减压储藏是当今先进的鲜活食品储藏保鲜技术.论述了减压储藏保鲜果蔬的基本原理及技术特点,在自制的减压冷藏保鲜仓中对油豆角进行了阶段性实验研究,描述了实验要领及过程,同气调储藏保鲜和普通冷藏保鲜效果进行了外观、质量、重量变化对比,对实验结果进行了客观的分析和总结.     

绿芦笋压差预冷和冷藏试验研究

试验研究了绿芦笋采后压差预冷和没预冷，用发泡聚苯乙烯箱和瓦楞纸箱包装，在2℃条件下冷藏10天、20天、30天、40天和50天的品质变化。结果表明：冷藏20天的绿芦笋新鲜并具有商品性。随着冷藏时间的延长，绿芦笋的失重率、腐烂率和顶端鳞片松散率逐渐增多，颜色变浅，可溶性固形物、维生素C和糖含量逐渐降低，叶绿素含量前期下降，中后期逐渐升高。压差预冷和包装方法对绿芦笋的保鲜效果影响较大。PC＋EPS的保鲜效果最好，不但能减少绿芦笋的失重率、腐烂率和顶端鳞片松散率，而且能减少其可溶性固形物、维生素C和糖含量的损失。     

移动式预冷设备在果蔬保鲜中的应用

本文讨论了发展移动式预冷设备的必要性,具体介绍了冰水预冷、注冰预冷、小型机械制冷冷库预冷、差压预冷、蓄冷板预冷、真空预冷、蒸发冷却预冷等实用的移动式预冷设备,指出移动式预冷设备在果蔬保鲜中具有广阔的应用前景。     

露天煤矿高温火区干冰降温试验研究

通过分析干冰(固态二氧化碳)性质,制定现场试验方案,采用干冰在露天煤矿高温火区内进行了炮孔局部降温试验。试验结果表明,干冰降温效果与孔深、孔温、干冰形状、与水的配合比例及注水顺序有关。高温炮孔注水后再注入干冰进行局部降温,当孔深小于8m时,孔底会形成1m左右的冻结段,能起到有效降温及维持低温效果的作用;当孔深超过8m时,孔底部温度降低,孔中部温度回弹速率较快,降温效果不佳。试验结论对进一步研究干冰降温方案有指导意义。     

新型荔枝气调保鲜箱研究

目前国内果蔬贮藏保鲜产业中产地与贮藏地间运输用的包装箱大多没有保鲜作用,本文介绍两种具有保鲜作用的新型气调保鲜箱,并通过该气调箱对荔枝保鲜效果的实验,分析其应用价值.通过实验结果表明,采用新型气调保鲜箱操作简便,果蔬保鲜效果优于冷藏保鲜,而成本与冷藏保鲜相当,应用前景广阔.     

孔庄煤矿集中降温方案的选择与优化

从孔庄煤矿井筒布置和矿井生产条件出发,先后总结、分析了片冰降温系统、热-电-乙二醇降温系统、井下低温水排热的井下集中降温系统(HEMS)和真空制冰降温系统。从集中降温方案效果、投资、降温系统运行稳定性、井筒输冷管路安装、矿井制冷水质、井下制冷排热等方面综合考虑,适合孔庄煤矿特点的集中降温途径只能是真空制冰降温方案,为矿井三期改扩建工程按期投产、验收创造了条件。同时,该降温工程的实施必将填补我国在矿井集中降温领域的一项技术空白,并在制冰技术、输冰管道、输冰工艺、压风冷却、井下融冰工艺、制冰节能技术上取得突破,进而推动我国煤矿降温制冷工艺的创新和发展。     

Infrared matrix-assisted laser desorption/ionization orthogonal-time-of-flight mass spectrometry employing a cooling stage and water ice as a matrix

Although water ice has been utilized in the past as a matrix for infrared matrix-assisted laser desorption/ionization mass spectrometry (IR-MALDI-MS), it has not found a wider use due to limitations in the analytical performance and technical demands on the employment of the necessary cooling stage. Here, we developed a temperature-controlled sample stage for use with an orthogonal time-of-flight mass spectrometer (MALDI-o-TOF-MS). The stage utilizes a combination of liquid nitrogen cooling and counterheating with a Peltier element. It allows adjustment of the sample temperature between ~-120 °C and room temperature. To identify optimal irradiation conditions for IR-MALDI with the water ice matrix, we first investigated the influence of excitation wavelength, varied between 2.7 and 3.1 μm, and laser fluence on the signal intensities of molecular substance P ions. These data suggest the involvement of transient melting of the ice during the laser pulse and primary energy deposition into liquid water. As a consequence, the best analytical performance is obtained at a wavelength corresponding to the absorption maximum of liquid water of about 2.94 μm. The current data significantly surpass the previously reported analytical features. The particular softness of the method is, for example, exemplified by the analysis of noncovalently bound holo-myoglobin and of ribonuclease B. This is also the first report demonstrating the analysis of an IgG monoclonal antibody (MW ~ 150 kDa) from a water ice matrix. Untypical for MALDI-MS, high charge states of multiply protonated species were moreover observed for some of the investigated peptides and even for lacto-N-fucopentaose II oligosaccharides. Using water ice as matrix is of particular interest for MALDI MS profiling and imaging applications since matrix-free spectra are produced. The MS and tandem MS analysis of metabolites directly from frozen food samples is demonstrated with the example of a strawberry fruit.     

水预冷及卷心菜冷水预冷的应用

水预冷技术在果蔬食品加工或储存中均非常关键。果蔬通过水预冷后，进入冷库储存或下一道加工环节，对于果蔬食品的储存与食物的品质起到明显的效果。本文通过卷心菜水预冷实际生产中的应用案例，简单扼要介绍了水预冷及优缺点、水预冷耗冷量计算及水预冷设计存在的难度和解决办法。     

北京市某区域集中供冷蓄冷系统的应用与分析

近年来,随着社会生产力的提高,区域集中供冷在我国取得了较快的发展。本文分析探讨了区域供冷中3种蓄冷方案(动态冰蓄冷、外融冰蓄冷、水蓄冷)的特点,并以北京市某区域供冷项目为例,介绍了3种蓄冷系统的规模、装机配置、组成等,同时进行了经济分析,提出了适合本项目的蓄冷方案:动态冰蓄冷系统与外融冰蓄冷系统耦合供冷。并就动态冰蓄冷方案中遇到的“冰堵”难点及蓄冰池蓄冷、蓄热出现的热胀冷缩安全问题提出了解决办法。对今后区域集中供冷系统的建设提供了参考。     

Refrigeration systems based on long-term storage of iceSystèmes frigorifiques s'appuyant sur le stockage de glace à long terme

A new refrigeration system with annual storage of ice, called the Ice Pond, has been developed and tested at Princeton University. The first commercial ice pond is now under construction to serve a 30 000 m³ office building in the Princeton area. This technique leads to substantial reductions in energy consumption with respect to conventional cooling and helps reduce summer peak electricity demand. In this article, the physics and engineering of ice production, preservation, and utilization are discussed. Experimental results of the Princeton research are reviewed. Finally, a method of economic analysis of the system is presented.     

Refrigeration systems based on long-term storage of ice

A new refrigeration system with annual storage of ice, called the Ice Pond, has been developed and tested at Princeton University. The first commercial ice pond is now under construction to serve a 30 000 m³ office building in the Princeton area. This technique leads to substantial reductions in energy consumption with respect to conventional cooling and helps reduce summer peak electricity demand. In this article, the physics and engineering of ice production, preservation, and utilization are discussed. Experimental results of the Princeton research are reviewed. Finally, a method of economic analysis of the system is presented.     

1000 ton per day ice plant for underground cooling at Harmony gold mine

Up to now all refrigeration plants used for mine cooling have used chilled water. When these refrigeration plants are situated on the surface, large quantities of water must be sent into the mine and pumped back to the surface again. It was suggested that a viable and economic alternative was to make ice on the surface and send this into the mine to reduce the quantity of water required. This Paper describes the world's first very large ice plant used for mine cooling. Ice from this plant is used to cool hot water originating at an underground fissure, and, in addition, provides cooling in the mine.