MATERIALS SCIENCE INITIATIVE SEMINAR: MATERIALS FOR TOMORROW October 13-15, 2010
Materials for Tomorrow is the first Initiative Seminar in Materials Science at Chalmers. The Materials Science Area of Advance was initiated in January this year as a result of allocation of substantial extra governmental funding to the area from the government. A number of outreach activities have been initiated at Chalmers in the field of materials science, and this workshop is the most important of these. The main aim of the meeting is to demonstrate the width of the on-going materials research at Chalmers. We are also pleased to have presentations from our External Advisory Board, five distinguished scientists in the materials field who are connected as advisers to Chalmers. The Materials Science Area of Advance also takes an active part in fostering an interest in science among young people and the first day of the meeting is dedicated to that topic. I hope you will find the workshop interesting and rewarding.
Krister Holmberg Director of the Materials Science Area of Advance
MATERIALS SCIENCE INITIATIVE SEMINAR: MATERIALS FOR TOMORROW October 13-15, 2010 PROGRAMME WEDNESDAY, OCTOBER 13 Time:
13.30 – 16.30
Kollektorn, MC2 Building
Day 1 of the workshop is a closed session targeted at high school students from the Gothenburg area. Short presentations by young scientists from Chalmers as well as from industry will be followed by practical demonstrations and hands-on experiences of new materials.
THURSDAY, OCTOBER 14 Time:
9.00 – 22.00
KC, Chemistry Building
SESSION 1: EXTERNAL ADVISORY BOARD Chair: Aleksandar Matic 9.00 – 9.10
Introduction (Krister Holmberg)
9.10 – 9.40
Alleviation of Stress: Design of Reactive Steels HARRY BHADESIA , DEPARTMENT OF MATERIALS SCIENCE AND METALLURGY, UNIVERSITY OF CAMBRIDGE, UK
9.40 – 10.10 Inorganic Nanocrystals: Emergence of New Chemical and Physical Properties Due to the Nanocrystals Ordering MARIE-PAULE PILENI, UNIVERSITY P&M CURIE, PARIS VI, FRANCE 10.10 – 10.30 Coffee
Chair: Peter Thomsen 10.30– 11.00 The role of first principle calculations in materials science BÖRJE JOHANSSON, ROYAL INSTITUTE OF TECHNOLOGY, STOCKHOLM, SWEDEN 11.00 – 11.30 Remote and Controlled Release from Thin Films and Capsules with Defined Nanostructure HELMUTH MÖHWALD, MAX PLANCK INSTITUTE OF COLLOIDS AND INTERFACES, POTSDAM, GERMANY 11.30 – 12.00 Regenerative Medicine and Its Challenges for Biomaterial Development JAMES KIRKPATRICK, INSTITUTE OF PATHOLOGY, JOHANNES GUTENBERG UNIVERSITY, MAINZ, GERMANY 12.00 – 13.30 Lunch
SESSION 2: SCIENCE HIGHLIGHTS AT CHALMERS Chair: Eva Olsson 13.30 – 14.00 Molecular Materials for Electronic and Renewable Energy Applications KASPER MOTH-POULSEN - CHALMERS ASSISTANT PROFESSOR IN MATERIALS SCIENCE 14.00 – 14.30 Materials for Health: Bioanalytical sensors based on supported cell membrane mimics: from virus detection to drug discovery FREDRIK HÖÖK, DEPARTMENT OF APPLIED PHYSICS 14.30 – 15.00 Materials for Energy Applications: New thermoelectric materials for heat recovery ANDERS PALMQVIST, DEPARTMENT OF CHEMICAL AND BIOLOGICAL ENGINEERING 15.00 – 15.20 Coffee Chair: Anders Palmqvist 15.20 – 15.50 Sustainable Materials: Processing and use of polymers from renewable materials – possibilities and limitations MIKAEL RIGDAHL, MATERIALS AND MANUFACTURING TECHNOLOGY
15.50 – 16.20 Experimental Methods: In-situ neutron diffraction studies using the pulsed spallation source ISIS STEN ERIKSSON, DEPARTMENT OF CHEMICAL AND BIOLOGICAL ENGINEERING 16.20 – 16.50 Theory and Modelling: From atoms to grain growth control in polycrystalline materials GÖRAN WAHNSTRÖM, DEPARTMENT OF APPLIED PHYSICS
POSTER SESSION & DINNER 16.50 – 18.30 Poster exhibition & refreshments. Tour of SOFT Microscopy Centre 18.30 – 22.00 Buffet dinner and entertainment
FRIDAY, OCTOBER 15 Time:
9.00 – 13.00
KC (9-10) and KE (10-13), Chemistry Building
SESSION 3: EXCELLENCE CENTRES IN MATERIALS SCIENCE Chair: Mikael Rigdahl 09.00 – 09.10 Welcome (Krister Holmberg, Chalmers) 09.10 – 09.50 VINN EXCELLENCE CENTRE BIOMATCELL Biomaterials – from Atom to Patient PETER THOMSEN AND JUKKA LAUSMAA, UNIVERSITY OF GOTHENBURG Free-form Fabrication of Medical Implants Using Electron Beam Melting ANDERS SNIS, ARCAM AB 09.50 – 10.20 Coffee
Chair: Göran Wahnström 10.20 – 11.00 VINN EXCELLENCE CENTRE SUMO BIOMATERIALS SuMo Biomaterials – a Vinn Excellence Centre Focused on the Intrinsic Relationship between Mass Transport and Microstructure in Soft Biomaterials MAGNUS NYDÉN, CHALMERS The Importance of the Relationship between Structure and Mass Transport in Pharmaceutical Materials CATHERINE BOISSIER, ASTRAZENECA AB 11.00 – 11.40 COMPETENCE CENTRE FOR CATALYSIS – KCK The Competence Centre for Catalysis – Advanced Materials for a Sustainable Society MAGNUS SKOGLUNDH, CHALMERS Modeling of materials for heterogeneous catalysis HENRIK GRÖNBECK, CHALMERS 11.40 – 12.20 COMPETENCE CENTRE FOR HIGH TEMPERATURE CORROSION – HTC Critical Materials Issues in the Production of Green Electricity – Corrosion in Power Boilers Burning Biomass and Waste LARS-GUNNAR JOHANSSON, CHALMERS Novel Materials for a New Generation of Solid Oxide Fuel Cells JAN-ERIK SVENSSON, CHALMERS 12.20 – 12.40 WALLENBERG WOOD SCIENCE CENTRE - WWSC Materials from Trees PAUL GATENHOLM, CHALMERS 12.20 – 12.40 Nanocellulose Biomaterials for Body Repair PAUL GATENHOLM, CHALMERS 13.00
PROGRAMME FOR DAY 1 (OCTOBER 13)
SPEAKERS: Martin Andersson, Chalmers University of Technology / Promimic Sverker Albertsson, Södra Innovation Carina Olsson, Chalmers University of Technology Kasper Moth-Paulsen, University of California at Berkeley/Chalmers University of Technology
HANDS-ON EXPERIENCES Inte papper, inte plast; Utan något mittemellan SVERKER ALBERTSSON, SÖDRA INNOVATION
Choklad – en smak av material NIKLAS LORÉN, CHALMERS
Smart House Paints Containing Microcapsules ALBERTA MOK, CHALMERS/CAPECO AB
Görs framtidens blöjor av trä? HANNA DE LA MOTTE AND FREDRIK WERNERSSON, CHALMERS, SCA AND SÖDRA
Mimicing Human Bone PAUL HANDA, PROMIMIC
Supraledare STEN ERIKSSON, CHALMERS
Byxor som inte går att smutsa ner (?) PER THORÉN AND SUSANNE WILKEN, CHALMERS
Mjuka material: långa molekyler och en massa oordning! JOHAN SJÖSTRÖM, CHALMERS
Välkommen till en resa in i en mikroskopisk värld STEFAN GUSTAFSSON, CHALMERS
Osseointegrated dental implants for lost tooth replacement OMAR OMAR, UNIVERSITY OF GOTHENBURG AND NOBEL BIOCARE
Vad gör katalysatorn i din bil? HANNA INGELSTEN, CHALMERS
POSTER SESSION October 14, 16.50 – 18.30 Posters are listed in alphabetical order according to first author’s last name
1. Designed nano-topography on implant surfaces for better bone surface integration: MG63 osteoblast-like cell responds to nano pits and nano bumps H.Agheli 1, A.Johansson 2, M.Johansson 2, S.Gustafsson3 and S.Petronis 1 1 Biological Physics Division, Applied Physics Dep., Chalmers Technical University, Sweden 2 Department of Biomaterials, University of Gothenburg, Sweden 3 Microscopy and Microanalysis Division, Applied Physics Dep., Chalmers Technical University, Sweden In last few years, we have seen increasing efforts to evaluate the influence of nanofabricated structures on biological systems and cell-surface interactions in particular. Nanofabrication technology combined with cell studies has opened new views on the mechanism of cell attachment and growth/differentiate on surfaces. Application of such nanofabrication technology, for example in tissue engineering, requires an understanding of the complex mechanisms occurring at such biointerfaces. One powerful approach, to simplify the experimental system, is to use model surfaces with controlled size and relief features to isolate and study the interaction with specific components in the biological system. This work is a small peace of a bigger project aiming to study and apply micro/nano topographical features on orthopaedic/dental implant surfaces for better bone-implant surface integration. The project is a creative combination of novel micro/nano fabrication routes, chemical/biochemical surface modifications, biomaterials and biological expertises in in vitro and in vivo biological studies. Colloidal lithography was used as nanofabrication technique, because it is a fast, inexpensive and versatile fabrication method, with the ability to fabricate large area (over cm2) surfaces and threedimensional (3D) implants and scaffolds. MG63 osteoblast –like cells were used in this part of the project since they were obtained from a human osteo-sacroma and are well characterized. They show many osteoblastic characteristic behavior that are typical of a relatively immature osteoblast, including the stimulation of alkaline phosphate activity, osteocalcin synthesis and inhibition of proliferation in response to treatment with vitamin D thus making a good model for experimenting the early stages of osteoblast differentiation. In this study we are aiming to compare biological reaction of MG63 cells cultured on flat surface versus the nanostructured surfaces containing nanosize bumps or pits.
2. Imidazole functionalized polymers complexed by Cu2+ and Zn2+; applications, coordination chemistry and the effect of substitution Markus Andersson,1,* and Magnus Nydén1 1
Department of Chemical and Biological Engineering, Applied Surface Chemistry, CHALMERS UNIVERSITY OF TECHNOLOGY, SE-41296 Göteborg, Sweden *e-mail: [email protected]
The addition of a pendant imidazole ligand moiety to a polymer backbone is an useful way of adding new functionalities to a macromolecule. Of special interest is the metal coordinating ability towards in particular Cu2+ and Zn2+ due to the intriguing macroscopic and microscopic properties of the resulting macromolecular complex. This has been utilized in our group for a variety of applications such as controlled release of active substances, stimuli responsive coating materials for triggered release and thin film formation utilizing a novel layer-by-layer technique [1,2]. Here we present some recent results concerning applications with both synthetic polymers and biopolymers.
Figure 1A) Schematic drawing of bilayer formation by coordinate crosslinking. B) Imidazole copper complex. σ-bond between the free electron pair of imidazole and the dx2-y2 orbital of Cu2+. Regarding the attachment of imidazole to a polymer backbone, there is a difference between synthetic polymers and biopolymers. Synthetic polymers are usually substituted at the pyrrole nitrogen whereas in biological systems, the imidazole ring is always substituted at position 4(5), with histidine as a prominent example, leaving the pyrrole nitrogen protonated. It is probable that Nature has chosen this particular position of substitution in order to tailor the coordinate interaction. To investigate the difference in coordination interactions two model compounds, 1-methylimidazole and 4(5)-methylimidazole, were investigated with NMR relaxation, EPR, far-FTIR vibrational spectroscopy, and ab initio calculations. It was found that the inductive/hyperconjugative effect of the methyl group has a much larger influence than the position of the group. The experimental findings were supported by the ab initio calculation of imidazole ligands with various electron withdrawing or electron donating substituents and their copper complexes. The results open opportunities to tailor the coordination interactions by changing chemical properties of the substituent attached to the imidazole molecule.  Fant, C.; Handa, P.; Nyden, M. J. Phys. Chem. B 2006, 110, 21808.  Hedin, J.; Isaksson, D.; Andersson, M.; Nyden, M. J. Colloid Interface Sci 2009, 336, 388.
3. Phase Separation of a Complex, Multiphase Tool Material using ELNES Acquired with DualEELS J. Angseryd1,2*, G. Kothleitner 3, M. Albu3, and H-.O. Andrén2 1
R&D at Sandvik Tooling, Stockholm, Sweden Department of Applied Physics/Microscopy and Microanalysis group at Chalmers University of Technology, Gothenburg, Sweden 3 The Institute for Electron Microscopy and Fine Structure Research (FELMI), Graz University of Technology, Graz, Austria *corresponding author: [email protected]
Advanced microscopy techniques have been used to investigate a polycrystalline cubic boron nitride (PCBN) tool material. PCBN materials are commonly used in hard turning operations of hardened steels. Its superior material properties, such as a very high hardness at the high cutting temperatures, make these types of materials ideal for today’s high manufacturing demands. To know the microstructure in detail provides the key to understand its behavior in machining operations. Transmission electron microscopy (TEM) techniques such as high angle annular dark field (HAADF) imaging and scanning (S)TEM electron energy loss spectroscopy (EELS), using the DualEELS setup, have been used in this investigation. DualEELS enables simultaneous data acquisition from the low loss region and the core loss region.[1-5] The simultaneous acquisition of data, starting from the zero loss peak and covering the entire core loss region, allows the user to always accurately correct for energy drifts and thus identify any edge onset energy shifts for various element edges in the spectrum. Spectrum imaging (SI) maps have been acquired from a commercial complex multiphase polycrystalline cubic boron nitride (PCBN) material. PCBN is a composite material where (~55 vol %) cubic boron nitride (cBN) grains are embedded in a polycrystalline and polyphase ceramic matrix. TiCN is the main phase in the matrix and the boundary region between larger TiCN grains and other phases has been studied here. The energy drift corrected spectra have been studied in detail for every element in each phase. By using ELNES signatures and the multiple linear least square (MLLS) fitting procedure, extraction of the SI maps for each element in every phase was done. Extracted bonding maps are presented in FIG. 1 and 2. References for each element have been used in the MLLS fitting procedure to obtain these bonding maps, providing a nice overview of the microstructure in the boundary region between larger TiCN grains and the other phases. As can be seen in FIG 2, TiB2 can be found on the grain boundaries of TiCN grains. Since TiB2 is a reaction product for these types of materials  and is formed during manufacturing, a reaction must have taken place between cBN and TiCN. Other phases found in the boundary regions are networks and larger areas of Al2O3 as well as AlN, both of which are also reaction products from the manufacturing.
References       
A. Gubbens et al., Ultramicroscopy. (2010), doi:10.1016/j.ultramic.2010.01.009. G. Kothleitner et al., Ultramicroscopy (2010) EDGE meeting proceedings, 62. M. Tencé et al., Ultramicroscopy (2010) EDGE meeting proceedings, 65. G.C. Trevor et al., Ultramicroscopy (2010) EDGE meeting proceedings, 61. J. Scott et al, Ultramicroscopy 108 (2008) 1586 J. Angseryd et al., International Journal of Refractory and Hard Metals, (2009). 27 (2), 249 This research is a collaboration between Sandvik Tooling, Chalmers University of Technology, Institute for Electron Microscopy and Fine Structure Research (FELMI) of the Graz University of Technology and supported by the Swedish Research Council.
4. Friedel-Crafts Alkylation of Sodium Salicylate with 4-tert-Butylbenzyl Chloride Performed in Aqueous Dispersions of Mesoporous Oxides Zebastian Bohström1, Hanna Härelind Ingelsten2, Krister Holmberg1 1
Applied Surface Chemistry, Chalmers University of Technology Competence Centre for Catalysis, Chalmers University of Technology
Reactant incompatibility is a common problem in organic chemistry. This study investigates the use of concentrated aqueous dispersions of mesoporous oxides to overcome incompatibility in the Friedel-Crafts reaction between sodium salicylate and 4-tertbutylbenzyl chloride, see Scheme I.
Scheme I. Friedel-Crafts alkylation of sodium salicylate with 4-tert-butylbenzyl chloride resulting in mono alkylation. The mesoporous material was first impregnated with the water-soluble nucleophile, sodium salicylate, and the “loaded” particles were then dispersed in the apolar electrophile, 4-tertbutylbenzyl chloride. A range of different mesoporous oxides and one clay mineral, montmorillonite, were investigated as catalyst for the reaction. These were all characterised with diffraction techniques (XRD and SAXS), IR and nitrogen adsorption isotherms (BET and BJH methods). Their Lewis and Brønsted acidity was determined by ammonia adsorption experiments using Diffuse Reflection Infrared Fourier Transform (DRIFT) spectroscopy as detection method. The reaction proceeded well and gave high yields provided proper stirring was maintained. Alumina and an aluminosilicate were the most efficient catalysts. These were also the materials that showed the strongest Lewis acidity. In general, there was good correlation between Lewis acidity and efficiency of the material as catalyst for the Friedel-Crafts alkylation. No correlation was found between specific surface area of the mesoporous materials and catalyst efficiency, however. Attempts to reuse tha catalyst were not entirely successful. A deactivation occurred after the first run. ESCA analysis indicated that the reduction in performance is due to adsorption of carbonaceous residues.
5. Structural Relaxation in binary Chalcogenide Glasses studied by Infrared Photon Correlation Spectroscopy Stefano Cazzato1,2, Tullio Scopigno1, Spyros N. Yannopoulos3 and Giancarlo Ruocco1 1
Dipartimento di Fisica and INFM, Università di Roma "Sapienza", I-00185 Roma, Italy. Department of Applied Physics, Chalmers University of Technology, S-412 96 Göteborg, Sweden, [email protected]
. 3 Foundation for Research and Technology Hellas, Institute of Chemical Engineering and High Temperature Chemical Processes, FORTH/ICE-HT, P.O. Box 1414, GR-26 504 Patras, Greece. 2
Dynamic Light Scattering studies of the structural relaxation of inorganic glass-formers have been limited in the past to a few oxide [1, 2] and halide glasses , in view of the negligible absorption that these glasses exhibit at visible wavelengths. This condition is not satisfied for many interesting glassforming systems that present strong absorption at visible wavelengths, as well as liquids exhibiting complex behaviors, such as pure sulfur and selenium. To overcome such limitation, we have recently developed a novel spectroscopic technique, namely Photon Correlation Spectroscopy with InfraRed radiation (IRPCS) . In this contribution an IRPCS investigation on chalcogenide glasses (ChGs) will be presented. Such systems contain at least one of the chalcogen elements: S, Se and Te, in conjunction with more electropositive elements, such as As, Ge, Sb, Si etc. ChGs have been shown to exhibit a dazzling variety of structural modifications (photo-structural changes) when exposed to light. This property of ChGs, that is, their sensitivity to light illumination, renders them ideally suitable media for many important applications (optical gratings, microlenses, waveguides, optical memories, holographic media, etc.). IRPCS has been applied in order to investigate the temperature and the exchanged momentum dependence of the relaxation dynamics of selected ChGs from the binary systems AsxSe100-x and AsxS100-x. We have thus been able to determine, as a function of As content, properties such as the glass transition temperature Tg, the supercooled liquid fragility, which is a measure of liquid's structure resistance upon heating, and the departure of the relaxation dynamics from the exponential (Debye) behavior. The present findings are compared with previous calorimetric and rheological experiments and discussed in the context of structural changes occurring in the glass structure upon increasing the As content, which changes the local dimensionality of the molecular units. References  S. N. Yannopoulos, G. N. Papatheodorou and G. Fytas, Physical Review B 60, 15131 (1999).  D. Sidebottom, R. Bergman, L. Börjesson, and L. M. Torell, Phyical Review Letters 71, 2260 (1993).  E. A. Pavlatou, S. N. Yannopoulos, G. N. Papatheodorou and G. Fytas, Journal of Physical Chemistry 101, 8748 (1997).  T. Scopigno, S. N. Yannopoulos, F. Scarponi, K. S. Andrikopoulos, D. Fioretto and G. Ruocco, Physical Review Letters 99, 025701 (2007).  A. V. Kolobov, editor, Wiley VCH, Berlin (2003).
6. Thermoelectric properties of Sb and Zn doped Ba8Ga16Ge30 clathrates D. Cederkrantz1, M. Nygren2 and A. E. C. Palmqvist1
Department of Chemical and Biological Engineering, Chalmers University of Technology, SE-41296 Göteborg, Sweden 2
Department of Inorganic Chemistry, University of Stockholm, SE-10691 Stockholm, Sweden
Ba8Ga16Ge30 is one of the best performing thermoelectric clathrates with ZT reaching 1.35 at 900 K for single crystal samples. In this work we have investigated the possibilities of further improving the performance of Ba8Ga16Ge30 by doping the system with Zn and Sb, respectively. A series of samples was prepared and doping was performed on either of the Ga and the Ge position. The synthesis and doping was done in one step through melt synthesis from the pure elements under vacuum. Powder XRD was used to establish that the clathrate type-I structure was achieved for all samples. Compaction by spark plasma sintering of the samples with small or no impurity phases was performed and >95% of theoretical density was reached for the compacts. Evaluation of thermoelectric properties of samples was performed between room temperature and 900K resulting in some unexpected behaviour. The figure-of-merit ZT was calculated from the measurements of electrical resistivity, thermal conductivity and Seebeck coefficient, and the impact of the doping on the material properties is discussed.
7. Evaluation of Surface Characteristics of Pre-alloyed Cr-Mo-Steel Powder D.Chasoglou1, L. Nyborg1, E.Hryha1
Department of Materials and Manufacturing Technology, Chalmers University of Technology, Ränvagen 2A, SE-412 96, Göteborg, Sweden. Tel: +46 31 772 1531, Fax: +46 31 772 3872, e-mail: dimitris.c[email protected]
, [email protected]
, [email protected]
A method for characterizing the oxide composition and distribution in both the surface and the interior of water-atomized powder was developed. Pre-alloyed powder with 3wt.% Cr and 0.5 wt.% Mo was chosen as the model material. Surface sensitive analytical techniques (high resolution electron microscopy in combination with EDX-analysis, X-ray photoelectron spectroscopy and Auger electron spectroscopy) were used in order to study the type, composition, morphology and distribution of oxide products. The analysis revealed that the powder particles were mainly covered by a homogeneous (~6 nm) thick Fe-oxide layer and some spherical particulate features with size up to 200 nm that were complex Fe-Cr-Mn-Si-oxides. Using EDX Smart-Maps tool, inclusions below 1μm in size and rich in Cr and Mn were observed rarely in the interior of the powder particles. By means of the method, the distribution of surface bound and bulk oxygen is realised.
Keywords: alloyed sintered steels, water atomized powder, surface oxides, internal oxides, XPS analysis, HR SEM+EDX analysis.
8. Water activities in bread during freezing and thawing: A thermal and dielectric study Guo Chena), Helén Janssona), Kaare F. Lustrupb) and Jan Swensona)
Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden; Lantmännen Food R&D, DK-2600 Glostrup, Denmark
The formation of ice is the primary cause for the quality deterioration in the frozen bread. This unfavorable phase transition is mechanistically correlated to the water activities in the complex bread material. In this study we investigated the water activities in the bread during freezing and thawing using differential scanning calorimetry, freezer freezing and dielectric relaxation spectroscopy. Four types of commercial bread containing different amount of sugar and dietary fiber were measured: Multikerneboller (low sugar, high fiber), Fuldkornsboller (medium sugar, high fiber), Krydderboller (high sugar, low fiber) and Huede Toast (low sugar, low fiber). The total water content in the fresh bread is ~40% by mass in Multikerneboller, Fuldkornsboller and Huede Toast but lower in Krydderboller (36%). The amount of freezable “free” water is also found to be lower in Krydderboller (~13%) than in the other three (~17-20%), so the amount of non-freezable bound water is similar in the four bread types (~20-23%). Ice formation starts at ~250 K; during the freezing process the bread suffers a mild mass loss due to the water diffusing outward and forming ice on the bread surface. The ice formed inside the bread features two preferential distributions in correlation to its spatial origins in the broadly size-dispersed bread pores. In Multikerneboller, Fuldkornsboller and Huede Toast the average ice size is estimated to be ~11 nm in the large pores and ~6 nm in the small ones; in Krydderboller the values are ~8 nm and ~4 nm, respectively. Besides, while the ice distributes in approximately equal amount inside the large and small pores in Multikerneboller and Fuldkornsboller, it forms in a larger amount inside the large pores in Krydderboller and Huede Toast. The sugar and fiber content appears to play a role in determining the distributions of the bread pores and hence the ice in the bread, though this role needs to be further clarified. The freezing (cooling) rate is found to only moderately affects the ice-forming activities in the bread and be most effective at