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51.
The use of dry whole milk, skimmed milk, caseinate, regular and modified whey, at 2% level (w/w) and with 2% additional protein level was studied in a chicken breast meat system with 51% water addition. At the 2% (w/w) level, all dairy proteins significantly reduced cooking loss compared with the control, with caseinate showing the best results. When compared on an equal protein level (2% total protein), the best performing ingredients were the whole milk and modified whey. A similar observation was made in their effect on the products’ hardness and fracturability. A cost analysis revealed that modified whey provided the most economical ingredient even when used in quantities three times greater than that of as caseinate. Microscopy results showed the formation of larger fine‐protein‐matrix regions in the treatments that provided higher fracturability values.  相似文献   
52.
Nowadays, customer orders with high product variety in small quantities are often received and requested for timely delivery. However, the order-picking process is a labour-intensive and costly activity to handle those small orders separately. In such cases, small orders are often grouped into batches so that two or more orders can be served at once to increase the picking efficiency and thus reduce the travel distance. In this paper, an order-picking operations system (OPOS) is proposed to assist the formulation of an order-picking plan and batch-handling sequence. The study integrates a mathematical model and fuzzy logic technique to divide the receiving orders into batches and prioritise the batch-handling sequence for picking, respectively. Through the proposed system, the order-picking process can be managed as batches with common picking locations to minimise the travel distance, and the batch-picking sequence can be determined as well. To demonstrate the use of the system, a case study in a third-party logistics warehouse is presented, and the result shows that both the order-picking activity and labour utilisation can be better organised.  相似文献   
53.
C.L. Choy 《Polymer》1977,18(10):984-1004
In this review we have concentrated on the interpretation of three essential aspects of the thermal conductivity K of polymers: the temperature dependence, the crystallinity dependence and the orientation effect. K for all amorphous polymers is approximately equal in magnitude and characterized by a T2 dependence below 0.5K, a plateau region between 5 and 15K and a slow increase at yet higher temperatures. While a number of models involving different phonon scattering mechanisms are capable of explaining these features, further corroborating evidence would be needed to explain the ad hoc assumptions involved. For semicrystalline polymers K shows both strong crystallinity and temperature dependence, with a distinctive cross-over point at about 10K. These marked features can now be understood as the result of the interplay between two competing factors: the intrinsically higher conductivity in the crystalline regions, and the reduction in K due to an additional phonon scattering mechanism which becomes important at low temperature. This scattering could arise from either the correlation in the spatial fluctuation of the sound velocity in the polymer or the acoustic mismatch at the interfaces between the crystallites and the amorphous matrix.Orientation produces a very large anisotropy in semicrystalline polymers, which however decreases at low temperature and becomes insignificant below 10K. This feature can again be understood in terms of the same competing mechanisms if one realizes that the molecular chains in the crystallites are essentially lined up along the direction of orientation thus offering very little thermal resistance along this direction. For polyethylene with an extrusion ratio of 25 the thermal conductivity at 100K along the extrusion direction is 91 mW/cm K, a value extremely high for polymers and close to that of stainless steel. At this temperature the anisotropy is only about 20, yet because of the different temperature dependence of the thermal conductivity along and perpendicular to the extrusion direction, we predict an anisotropy as high as 60 at room temperature.  相似文献   
54.
对T300碳纤维增强QY8911双马来酰亚胺树脂十字叠层复合材料的冲击损伤与破坏特性进行了实验研究。采用落锤(自由落体)冲击试验方法,测定了三类铺层结构板材的冲击破坏强度和冲击损伤能量门槛值;将冲击强度与破坏模式和静态三点弯曲情况做了对比。用宏、细观方法检测了冲击损伤特性。对低于门槛值的冲击动力学行为给出了分析模型。  相似文献   
55.
This paper studies the wireless two-way relay channel (TWRC), where two source nodes, S1 and S2, exchange information through an assisting relay node, R. It is assumed that R receives the sum signal from S1 and S2 in one timeslot, and then amplifies and forwards the received signal to both S1 and S2 in the next time-slot. By applying the principle of analogue network coding (ANC), each of S1 and S2 cancels the so-called "self-interference" in the received signal from R and then decodes the desired message. Assuming that S1 and S2 are each equipped with a single antenna and R with multi-antennas, this paper analyzes the capacity region of the ANC-based TWRC with linear processing (beamforming) at R. The capacity region contains all the achievable bidirectional rate-pairs of S1 and S2 under the given transmit power constraints at S1, S2, and R. We present the optimal relay beamforming structure as well as an efficient algorithm to compute the optimal beamforming matrix based on convex optimization techniques. Low-complexity suboptimal relay beamforming schemes are also presented, and their achievable rates are compared against the capacity with the optimal scheme.  相似文献   
56.
The surface of layered double hydroxide nanoparticles, a potential drug‐delivery nanovehicle, is modified with the cancer‐cell‐specific ligand, folic acid. The surface modification is successfully accomplished through step‐by‐step coupling reactions with aminopropyltriethoxysilane and 1‐ethyl‐3‐(3‐dimethyl aminopropyl)‐carbodiimide. In order to evaluate the cancer‐cell targeting effect of folic‐acid‐grafted layered double hydroxide utilizing fluorescence‐related assay, both layered double hydroxide with and without folic acid moiety are labeled with fluorescein 5′‐isothiocyanate. The uptake of layered double hydroxide and folic acid conjugated into KB and A549 cells is visualized using fluorescence microscopy and measured by flow cytometry. Both chemical and biological assay results demonstrate that the folic acid molecules are indeed conjugated to the surface of layered double hydroxide and thus the selectivity of nanovehicles to cancer cells overexpressing folate receptors increases. In this study, it is suggested that layered double hydroxide nanoparticles can be used as drug‐delivery carriers with a targeting function due to the chemical conjugation with specific ligand.  相似文献   
57.
The plate silencer [1] that consists of an expansion chamber with two side-branch cavities covered by a light panel can achieve a desirable noise reduction in broadband theoretically. The concept is similar to drum silencer [Choy YS, Huang L. Experimental studies of drum-like silencer. J Acoust Soc Am 2002;112:2026–35]. To attain optimal noise reduction, either the membrane of the silencer should be of minimal weight while retaining very high tensile strength or the panel should be kept at very high bending stiffness that is dependent on its geometry and mechanical properties. To achieve such goal, various kinds of composite system such as carbon fibres or aluminum were mounted on light core foam to build a noise reflection panel. A design of composite panels which can provide a reduction in panel weight as well as enhance the bending stiffness, is introduced in this paper. Predictions of the new model are to be compared with the normal foam plate in the aspects of noise reflection capability and performance of noise abatement apart from the material properties.  相似文献   
58.
Monodisperse ethyl cellulose (EC) microspheres (MSs) of three size groups (20–35, 55–60, and 80–105 μm in diameter) were fabricated to study the effect of the MS size on the drug‐release profiles with a novel scheme combining mechanical and hydrodynamic forces. More than 90% of the MSs were within ±3 μm of the average diameter, regardless of the EC viscosities used in the study. The effect of the polymer viscosity was also examined with ECs with two distinct viscosities (4 and 45 cp). The encapsulation efficiencies (EEs) of piroxicam and rhodamine were 6.4–51 and 63–80%, respectively. The drug distribution in the MSs showed a higher concentration near the particle surface, and this was more distinct with rhodamine. An approximately zero‐order release was observed with the small MSs of 4‐cp EC during 24 h without evident initial bursts. The MS size affected the surface‐area‐to‐volume ratio, EE, and intraparticle drug distribution, affecting the drug‐release profiles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
59.
BACKGROUND: The aim of this trial was to compare the outcome achieved with neoadjuvant chemotherapy followed by radiotherapy to that achieved with radiotherapy alone for patients with locoregionally advanced undifferentiated or poorly differentiated nasopharyngeal carcinoma (NPC) meeting one of the following criteria: Ho's T3 disease, Ho's N2-N3 disease, or lymph node size > or =3 cm. METHODS: Between September 1989 and August 1993, 334 patients were enrolled in the study, with equal numbers of patients randomized to the neoadjuvant chemotherapy arm (CT arm) and the radiotherapy arm (RT arm). Neoadjuvant chemotherapy consisting of 2-3 cycles of cisplatin (60 mg/m2 on Day 1) and epirubicin (110 mg/m2 on Day 1) followed by radiotherapy was given to the CT arm. For radiotherapy, a dose of 66-74 gray (Gy) (median, 71 Gy) was delivered to the primary tumor and 60-76 Gy (median, 66 Gy) to the neck. Two hundred eighty-six eligible patients completed the treatment and were evaluable for treatment response (134 in the CT arm, 152 in the RT arm). All patients were included in the survival analysis based on the intention to treat. The median follow-up was 30 months for the whole cohort and 41 months for the surviving patients. RESULTS: Analysis of the 334 patients based on the intention to treat showed no significant difference in relapse free survival (RFS) or overall survival (OS) between the 2 treatment arms (3-year RFS rate: 48% in the CT arm vs. 42% in the RT arm, P = 0.45; 3-year OS rate: 78% vs. 71%, P = 0.57). In an efficacy analysis based on only the 286 evaluable patients, a trend of improved RFS favoring the CT arm was observed (3-year RFS rate: 58% vs. 46%, P = 0.053), with again no significant difference in OS (3-year OS rate: 80% vs. 72%, P = 0.21). In the subgroup of 49 patients with bulky neck lymph nodes >6 cm, improved RFS (3-year RFS rate: 63% vs. 28%, P = 0.026) and OS (3-year OS rate: 73% vs. 37%, P = 0.057) were observed, favoring the CT arm. CONCLUSIONS: This multicenter randomized study did not demonstrate any benefit with the addition of cisplatin-epirubicin neoadjuvant chemotherapy for patients with locoregionally advanced nasopharyngeal carcinoma; therefore routine administration of neoadjuvant chemotherapy to this target group cannot be recommended. Although the overall incidence of recurrence was reduced with the addition of chemotherapy in the efficacy analysis, the overall survival was not affected. A more effective chemotherapy regimen, the selection of an appropriate target group, and the use of an alternative strategy for combining chemoradiotherapy should be explored in future trials.  相似文献   
60.
A clay-drug nanohybrid was prepared by interfacial boundary ion exchange reaction, from which the release mechanism of a poorly water soluble drug, itraconazole, was studied systematically. The effect of cation types on drug release was investigated on the basis of a UPS 25 guide line and the effect of Laponite dissolution was also studied at pH = 1.2. To describe the release patterns, mathematical modeling was preformed using first-order, Elovich, parabolic diffusion, and power function equations.  相似文献   
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