Protein and energy concentrations of meat meal and meat and bone meal fed to pigs based on in vitro assays

The objective of this study was to develop equations for estimating ileal digestible crude protein (CP) and metabolizable energy (ME) contents of meat meal (MM) and meat and bone meal (MBM) as feed ingredients for pigs based on in vitro assays. Test ingredients were 4 sources of MM and 3 sources of MBM. Ash and CP contents of the ingredients ranged from 3.8% to 33.1% and 46.8% to 82.9% (as-is basis), respectively. In vitro ileal disappearance (IVID) of CP was determined and ileal digestible CP content was calculated by multiplying CP content by IVID of CP. In vitro total tract disappearance (IVTTD) of dry matter (DM) was determined and ME was calculated using gross energy, CP contents, and IVTTD of DM. The IVID of CP and IVTTD of DM ranged from 77.2% to 88.7% and from 82.7% to 92.4%, respectively. Calculated ileal digestible CP and ME contents ranged from 37.8% to 73.5% DM and 2,405 to 3,905 kcal/kg DM, respectively. Ash contents were negatively correlated (P < 0.001) with CP (r = −0.99), in vitro ileal digestible CP (r = −0.97), gross energy (r = −1.00), in vitro digestible energy (r = −0.97), and adjusted ME (r = −0.97). The most fitting equations for ileal digestible CP and adjusted ME were: ileal digestible CP (% DM) = 11.91 − 0.90 × Ash (% DM) + 0.74 × IVID of CP (%) (R² = 0.99) and adjusted ME (kcal/kg DM) = 130.85 − 50.90 × ash (% DM) + 47.06 × IVTTD of DM (%) (R² = 0.99). To validate the accuracy of the prediction equations for ME, mean bias and linear bias were determined using a regression analysis. Calculated ME values of MM and MBM were in a good agreement with data obtained from animal experiments based on a statistically insignificant bias in the models. In conclusion, ME concentrations of MM and MBM as swine feed ingredients can be calculated using ash concentration and in vitro disappearance of dry matter.     

地温空调井抽回灌效果影响关键因子识别

为了探析引起地温空调井抽回灌效果的主要制约因素,通过单相关系数分析、主成分绝对得分的源解析模型、拟合度检验和多元线性回归的方法分析影响单井回灌效率的影响因素。结果表明:井径、滤水管孔隙率及抽回灌井数比与单井回灌效率的相关性和拟合度较好,故将井径、滤水管孔隙率及抽回灌井数比作为影响单井回灌效率的关键因子,同时分析了单井回灌效率与关键因子的之间的拟合方程及多元线性回归方程,得到了单井回灌效率与关键因子之间的定量关系。     

Experiment for Condensing Heat Transfer Performance in a New Type of Horizontal Three Dimensional Inner Microfin Tubes

A new type of three dimenstional inner microfin tube is devoloped. Under four different pressures and in the range of condensing mass velocities from 33 to 153 kg/m2 . s,and by the experimental study of the three kinds of tubes with different microfin parameters, the performances of the condensation heat transfer for R11 in the horizontal microfin tubes and obtained. The experiments show that the inner microfin tube is a hopeful and nighty effective condensing heat transfer enhancement tube.     

Study on Landscape Planning of Mourtcainous City

:In accordance with the problems, occurred in the mountainous city's construction, especially the crises such as the destruction of ecological and humanistic environment, the loss of traditional culture and characteristics and the disorder of urban structure, this paper discusses the distinctive landscape characteristic of mountainous city thoroughly.     

A STUDY ON HEAT AND MOISTURE STATE OF HULL LAYER FOR THERMAL INSTULATION OF A COLD STORAGE

This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance.     

活性多肽提取分离方法研究进展

综述了近几年来生物活性多肽物质的分离和提纯方法,主要包括色谱、电泳等方法,以及这些方法在肽类研究中的应用现状。     

论压弯构件

钢筋混凝土轴心受力构件、受弯构件和偏心受压构件在力学行为上有一个共同的特征,即构件的材料纤维均处于单向应力状态。为便于分析比较,特将这三类构件的力学性能一起讨论。     

优质独本菊和多头菊规模化栽培技术试验

以独本菊和多头菊为研究对象,对其进行了育苗和栽培试验。结果表明:间歇式全光雾照扦插出的苗品质好,省时省事,B9和多效唑结合使用矮化效果好,且垄作套盆比平地套盆栽培效果好,有利于规模化生产。