iran is a major world producer of walnuts and a hub of walnut exports to other countries. walnut harvesting and cracking is still done manually, which increases price and waste. design and development of an effective harvester and walnut crusher is required to reduce costs and wastage. this study determined the mechanical properties of a test apparatus employing two flat jaws using different tr...

this study was carried out to determine the effect of seed growing regions and loading speed on some mechanical properties of castor seed. these properties are used to design and improve related machines such as expeller that are used for extraction of oil from castor seed. mechanical properties of castor seed were expressed in terms of rupture force and energy, bio-yield force, apparent modulu...

mechanical properties of grain are influenced by various factors including soil nutrients and grain moisture content at harvest time. in order to reduce mechanical losses, the design of different processing operations should be performed based on the knowledge of factors influencing the mechanical properties. the effects of urea fertilization methods and grain moisture content at harvest time o...

agricultural products are affected by static and dynamic forces at different stages of harvesting, handling and processing. in most cases, the damages are inflicted upon raw products. in the present study the mechanical properties of tomato fruits were found out for two cultivars (super bta and petoerly ch), during 4 periods of time (1, 5, 10 and 15 days past harvest), and at two levels of frui...

Dynamic force spectroscopy of single molecules is described by a model that predicts a distribution of rupture forces, the corresponding mean rupture force, and variance, which are all amenable to experimental tests. The distribution has a pronounced asymmetry, which has recently been observed experimentally. The mean rupture force follows a (lnV)2/3 dependence on the pulling velocity, V, and d...

We simultaneously measure conductance and force across nanoscale junctions. A new, two-dimensional histogram technique is introduced to statistically extract bond rupture forces from a large data set of individual junction elongation traces. For the case of Au point contacts, we find a rupture force of 1.4 ± 0.2 nN, which is in good agreement with previous measurements. We then study systematic...

Single-molecule mechanical manipulation has enabled the quantitative understanding of the kinetics of bond ruptures as well as protein unfolding mechanism. Single-molecule experiments with theoretical models have allowed one to gain insight into free energy landscape for chemical bond and/or protein folding. For mechanically induced bond rupture, the bond-rupture kinetics may be governed by loa...

abstractin this study, the tensile force requirement, to separate the grain paddy was measured. the velocities of grain paddy it 100, 200, 300, 400, and 500 mm/min, and force requirement to failure stem at 100, 300, and 500 mm/min velocities was measured by using instron device. the data was analyzed using a completely randomized design. the results showed that velocity had a significant effect...

The problem of diffusive bond dissociation in a double well potential under application of an external force is scrutinized. We compute the probability distribution of rupture forces and present a detailed discussion of the influence of finite rebinding probabilities on the dynamic force spectrum. In particular, we focus on barrier crossing upon extension, i.e., under linearly increased load, a...